M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Engine management => Topic started by: bmwman91 on November 22, 2020, 11:36:40 PM
-
I am going to document my ECU conversion as it progresses over the next few months and share as much info as possible.
First, which ECU am I going to be running? It is the BMWLink E36X, which is a Motronic form-factor version of Link's G4X XtremeX product. The G4X line was released around the beginning of 2019 and is their current latest-and-greatest platform. The XtremeX is the 2nd highest-tier ECU in that line. As far as "enthusiast" grade ECUs go, it is one of the better ones out there spec-wise, with AEM Infinity products being IMO the main competitor (not that it matters...Motronic has an 8 bit MCU running at 1MHz...basically everything on the market now runs 100-200MHz and on 16 or 32 bit cores).
E36X ECU: https://dealers.linkecu.com/E36X_2
G4X XtremeX specs: http://linkecu.com/documentation/XtremeXPlugInECUSpecs.pdf
These seem to retail for $1000-1100 at US dealers. That is VERY affordable for a quality aftermarket ECU. It is still what I'd consider an enthusiast-grade ECU, although plenty of racers use Link. "Real" motorsport-grade ones usually start at $4000 as a bare minimum, and have a ton of features that I have no need for (the M42 is a very simple engine compared to modern performance engines). Even better, it uses the same 88 pin connector as the M42's Motronic 1.7 ECU, so I really just need to move some terminals around and add new wires for the features I will add. It was a close call between this and the AEM Infinity 506, but the AEM ECU had a top-entry connector that I disliked since it would not work well with the factory ECU mount location, and it would require me to either use external ignition coil drivers, or change over to newer ones with built-in drivers (which would have been fine, but a bit more wiring work). I only recently became aware of the E36X, and it checked all of the boxes I cared about. For the M20 folks out there, the 88 pin connector used by M1.7 can be bought new at a number of places (quite a few motorsport ECUs use it as it turns out), and it uses the same terminals as the 55 pin connector on M1.3, so you could actually swap it right onto your harness if you get the terminal extraction tools.
Regarding connectors and terminals, I will try to keep this post updated with part numbers as I accumulate them. Nearly every connector on our wire harnesses is a commercially available part from TE/Amphenol, from their various "Timer" series. The Motronic connectors use Micro Timer 1 and Junior Power Timer terminals, almost the entire rest of the harness uses Junior Power Timer terminals and housings, and (at least on the M42) the ignition coil connectors use Standard Power Timer terminals. You'll note that the technical drawings/datasheets for these have a zillion different variants. Most are unavailable, and the ones below were among the few that were both the correct type and still available on the web. This applies to all of the terminals listed below. BMW also has PNs for all of them, but they also mark them up heinously, so I only list those when it's the only option.
COMMON TERMINALS / CONTACTS
Micro Timer 1 female terminals: TE PN 929952-1 (for 0.5-1.0mm^2 wires)
So far this is the only problematic one...it is very likely out of production, and there is only one place that I have found which still stocks them. Micro Timer 2 & 3 terminals won't work in the Motronic connector as far as I can tell. I bought way more than I needed so as to have spares, and I got them here:
https://www.onlinecomponents.com/te-connectivity-amp-brand/9299521-10530804.html
I have also seen PN 929927-1, which takes 0.2-0.5mm^2 wires, available at a few places in the UK.
Junior Power Timer female terminals: TE PN 927771-3 (for 0.5-1.0mm^2 wires), 927768-3 (for 1.0-2.5mm^2 wires)
Used on the larger Motronic connector terminals, and nearly everywhere else in the harness where a rectangular housing is found.
Standard Power Timer female terminals: TE PN 927831-2 (for 0.5-1.0mm^2 wires), 927837-2 (for 1.0-2.5mm^2 wires)
These are used on the M42's ignition coils, as well as in the relay sockets up on the firewall.
2.5mm round male terminals: TE PN 929963-1 (for 0.5-1.0mm^2 wires), 929964-1 (for 1.0-2.5mm^2 wires)
Used in many of the same places listed for the female terminals below.
2.5mm round female terminals: TE PN 929970-1 (for 0.5-1.0mm^2 wires), 929971-1 (for 1.0-2.5mm^2 wires)
At least on the M42, these are used in the AFM connector and O2 sensor connector, C101, diagnostic plug, as well as in various places in the chassis wiring.
COMMON CONNECTOR HOUSINGS
2 position compact receptacle, Junior Power Timer (JPT): TE PN 1-825414-5
Used on the M42's fuel injector sub-harness. There is another PN, 826008-5, which looks similar but will not work on the injectors. It lacks the cut-out needed to clear the injector body, so don't buy that one.
2 position receptacle, JPT: TE PN 827551-3
This one is on the ICV, oil pressure switch, temperature gauge sender and some other places.
3 position receptacle: TE PN 1-827578-1
This is found on the M42 TPS, the M20 ICV, and a few other places.
7 position round connector housing. The TE parts are not available, but BMW parts dealers seem to have them.
Male housing: BMW PN 12521718125
Female housing: BMW PN 12521718126
Female housing lock ring for panel-mounting: BMW PN 12521718127
90deg rubber boot: BMW PN 12521737944
The male & female housings are used on the M42's AFM connector, and on the M20's fuel injector harness connector. I can't find the PN for the straight boot at the moment.
Other JPT connectors: Search around online for Junior Power Timer connectors and you'll see a bunch of the other ones with 2-7 positions. There are really too many to list here since, at least for this project, I don't need them all.
88 pin "Motronic" connector, with a few places that I found it for sale. Not cheap, and you could probably find a hacked-off one on eBay for a lot less (just de-pin it and you are good to go). M42 owners don't really need to worry about this since we already have one!
https://prowireusa.com/p-2487-88-way-bosch-connector-kit.aspx
https://www.automotiveconnectors.com/88-way-boch-ecu-connector-housing-assembly.html
https://www.msel.co.nz/epages/motorsportelectronics.sf/en_US/?ObjectPath=/Shops/motorsportelectronics/Products/CONAMP88K
https://racecal.co.uk/products/bosch-88-way-connector-terminals
A catalog for the 88-pin series of plugs: https://www.dalroad.com/wp-content/uploads/2015/05/88way-plug-in-connection.pdf
To crimp the terminals, you will want to get some decent crimpers. There are generic ones out there that work reasonably well, although they don't make the crimps as nicely as the factory did. Although I use different ones, these look like cheap ones that would work well with all of the terminals above:
https://www.amazon.com/IWISS-Barrel-Terminal-Crimper-Terminals/dp/B07476C1LD/
Personally, ratcheting ones are a lot more pleasant to use and this looks like a decent cheap setup:
https://www.amazon.com/IWISS-Ratcheting-Crimping-Tool-Non-Insulated/dp/B08DRCRRCQ/
For terminal extraction, this is the kit that I have. It has many more than are needed for this connector system, but I have lots of projects so it's fine for me. There are a bunch of cheaper copycat kits of this out there now, and they are all just as good. Don't buy any of the really cheap sets that look like a bunch of keys on a ring...they are not going to work well at all.
https://www.amazon.com/Performance-Tool-W89732-Terminal-Release/dp/B00EDEEICA/
I am working out the initial plans for the wiring harness modifications, and it is all still pretty rough since Link tech support needs to get back to me on a couple of questions, and I need to decide which new features actually matter enough to add. I'll post up a big table of the stock & new pinouts for things when I finalize it in the next week or two. Additionally, some of you may recall the big full-color complete M42 wire harness drawing I made a while back. I'll be making another one of those to fully document the new and improved one.
To finish, as if there is not enough to read already, here is the list of "improvements" I plan to incorporate with this ECU:
1) Dual knock sensing. The M42 block already has 2 threaded bosses for knock sensors which were added in the E36, so I just need to buy them and bolt them on (plus add wiring).
2) Full sequential injection. Motronic 1.3 & 1.7 were set up to fire the injectors in two groups. I will be adding the necessary wiring to fire all of them individually.
3) MAP-based load measurement. No more AFM (or in my case, MAF).
4) Closed loop feedback using a wide-band O2 sensor.
5) Traction control, or at least limited traction control. I can pull wheel speed signals from the ABS unit, and the ECU can do some limited torque management without an electronic throttle. Call E-throttle 5b...I may look into some variant of this if I have enough IO's left.
6) M50 ICV. This should lead to a nicer idle than the M42's very basic PWM valve.
7) Logging oil pressure & temperature, fuel pressure & exhaust gas temperature (all 4 cylinders individually, using an external TC DAQ via CAN).
That's it for now. I'm going to take a break from thinking about this and go relax for the rest of the evening!
-
Here's an update for today, since I had a chance to do some poking around with the wheel speed signal sensors and a $20 eBay ABS computer. It turns out that bench-testing these things is not simple. They have extensive fault detection routines that run at start-up, and in the event of a fault they will basically not power themselves up enough to do any sort of meaningful testing. I'd have to connect some dummy relays and resistors to mimic the ABS pump. So, other than that I just used this thing to trace out the input circuitry for the wheel speed sensors and make sure that nothing there might get upset if I tapped into the signal lines externally.
(http://www.e30tuner.com/assist/e36x/e36x004.jpg)
I did pull the cover off of the one in the car and probed it with the rear wheels lifted and the engine idling in gear. The 16 pin DIP IC in the middle is the signal "conditioner" that takes the VR sensor signal and turns it into a 5V TTL signal. The 3rd pin in from each corner is the TTL output, with the 4 corner pins themselves taking in the VR sensor signal. The simplest solution for my ECU project would be to tap into those TTL signals, but I have no desire to go mucking around with the ABS computer. While the chances of causing it to malfunction are small, I don't want to chance it.
So, the way I plan to go is with some MAX9926 chips. I had this little board from a data logger I had installed in a spare Motronic, which has a MAX9926 on it. I soldered some new wires onto it and tapped into the ABS computer connector (shoved stripped wire ends into terminal slots).
(http://www.e30tuner.com/assist/e36x/e36x005.jpg)
(http://www.e30tuner.com/assist/e36x/e36x006.jpg)
The connector itself is very easy to work with, and popping the terminals out / replacing them with double-wires later will be nice and easy I think.
(http://www.e30tuner.com/assist/e36x/e36x007.jpg)
I got the oscilloscope on the two rear wheels' sensor signals, plus the output of the MAX9926, to verify that I would get a clean TTL signal, and that the introduction of the MAX9926 was not causing any sort of issue or change in the VR sensor signal that the ABS computer also relied on. Here is what it looks like in first gear at idle. Yellow is the right-rear wheel, and green is the left-rear which also had the MAX9926 tapped into it.
(http://www.e30tuner.com/assist/e36x/e36x001.png)
Here's ~10MPH...
(http://www.e30tuner.com/assist/e36x/e36x002.png)
And ~45MPH...
(http://www.e30tuner.com/assist/e36x/e36x003.png)
The other thing I was curious about was any voltage difference between the ECU ground (on the battery tray) and the ABS computer ground (up under the dash). The multimeter showed a negligible difference with RMS averaging.
(http://www.e30tuner.com/assist/e36x/e36x008.jpg)
The oscilloscope showed significant, but extremely brief, transient spikes. This is from the ignition, and the peak value was influenced by how I routed the wire from the ECU ground over to the ABS computer. So, at least some of this is driven by EMI in the long extension wire. Anyway, this is ~1-20MHz noise, which should be a non-issue with any reasonable amount of bypass capacitance installed in the VR conditioner circuit I'll make.
(http://www.e30tuner.com/assist/e36x/e36x004.png)
Other than that, I received the E36X today. It is a nice little unit with full conformal coating all over (looks like they dipped the 2 boards separately before assembling them, while being careful not to get it in the connectors). The large ignition coil driver ICs are placed intelligently near pin 55, which is the dedicated ignition ground connection. This thing is intended to run an M50, so any M20 folks here who want to go full COP could definitely use this thing. A big part of this thing's appeal is the fact that it'll drive the coils directly, negating the need for a "smart coil" conversion or any sort of external coil driver module.
(http://www.e30tuner.com/assist/e36x/e36x001.jpg)
Part of me was tempted to plan to void the warranty and solder wires between all of the "extra" connections and the unused pins on the Motronic connector, but I need to make a hole in the ECU case to run the MAP line anyway, so I think I'll just leave well enough alone. Although...I could run an external MAP sensor and connect its output to a spare analog input so that everything is routed through a single main loom...must resist the urge to immediately hack-up my new toy.
(http://www.e30tuner.com/assist/e36x/e36x002.jpg)
(http://www.e30tuner.com/assist/e36x/e36x003.jpg)
Other than that, I got out some of my spare Motronic bits and did a quick bench test to ensure that it was functioning and talking to my computer.
(http://www.e30tuner.com/assist/e36x/e36x009.jpg)
That's it for today. There will be plenty more TMI updates as I continue to work on this!
-
I'm amazed at what you can do and your knowledge of all this (to me) voo doo.
-
That's awesome!!! Keep up the great work!
Cheers,
~Ralph
-
Thanks guys, hopefully this will be an informative thread for folks. I have a parallel copy going on over at r3v too.
So I played around a bit more with the oscilloscope and MAX9926 board today. This time I connected it to the wheel speed sensor inputs, but ran the engine with the wheels stopped. I'll need to work a bit on some filtering and changing threshold voltages since I was getting a good amount of ignition-driven false triggers. The MAX9926 is pretty configurable, and the little board I bought is by default set up to (basically) run at maximum sensitivity. It can be configured to have a higher minimum threshold before it'll trigger, and the input can be low-pass filtered to reject stuff like the ~10MHz ignition noise pulses.
Here's a false trigger with everything grounded at the ABS computer. Blocks of these pulses were occurring at ~30Hz at idle, which coincides with 900RPM, so it is most likely a product of the ignition system. Fuel injectors could also be making some noise since they produce ~80V flyback spikes when they close, which are clamped by the driver ICs in the ECU and dumped to ground. ignore the cursor measurements, I forgot to turn them off.
(http://www.e30tuner.com/assist/e36x/e36x005.png)
I captured a bunch of these, and while many had spikes from the ignition, some were triggered by ~200mV drift in the wheel speed sensor voltage (the MAX9926 is VERY sensitive when set up to be). Based on my signal captures, the wheel speed sensors put out ~2Vp-p with the car idling in first gear, which is SLOW, so I could probably set 1.5V as a minimum threshold and be good.
Here is what it looks like with the oscilloscope grounded at the ECU, and the MAX9926 still connected over at the ABS computer. Basically, this is what the ECU would "see" coming from it, although I suspect that some of the extra noise spikes are EMI being picked up by the 4ft ground wire I ran from the ECU ground point to the driver's footwell. Everything starts acting like an antenna to some degree.
(http://www.e30tuner.com/assist/e36x/e36x006.png)
Here's that big noise spike, zoomed in. Again, this is mainly >10MHz noise here, and based on measurements with the wheels moving I think that the wheel speed signal will be ~1600Hz at like 150MPH, so I can definitely put some low pass filtering on the MAX9926 input.
(http://www.e30tuner.com/assist/e36x/e36x007.png)
Other than that, it's back to work tomorrow and I think that the remainder of 2020 will be fairly busy for me. Progress on this may be slower than I like, but I will keep the updates coming.
-
I am basically done with the wheel speed signal investigation stuff today. I had some spare components laying around and redesigned the input to the MAX9926 so that it would much more effectively filter noise out. You may be wondering why I am starting out putting so much effort into setting up the signals for traction control, since it is probably the least necessary part of this project. Well, it's sort of the only part that is "new" to me in terms of the electrical stuff. Some of you may recall my Motronic reverse engineering thread, and my engine harness rebuild earlier this year...there's not much mystery there for me, so I am just tackling the thing I am least familiar with first.
Anyway, I swapped out the 1nF cap that this little board came with for an 8.2nF cap in my spare parts pile. That went on the positive input line after the 10K resistor. For the negative input line, I jumped it directly to ground (bypassed the 10K resistor) since the second wire of the wheel speed sensors is also grounded. If both were actually usable, this never would have been an issue to begin with since the MAX9926 works a hell of a lot better with differential signals, but oh well, the E30 is old and just designed that way. For the 4 channel board I will design for the permanent install, I will probably make the low pass filter even more aggressive since I only need it to work for an input of 2kHz (that's like 180MPH...which is a lot faster than the car can go).
(http://www.e30tuner.com/assist/e36x/e36x010.jpg)
After hacking together the changes I went back out, removed the knee bolster and shoved the wires into the rear of the ABS plug's terminals yet again. The result was ZERO false triggers with the car running. The ignition noise spikes were still there of course, but the disturbances they created were of too small an amplitude and too high a frequency to trigger the MAX9926. The noise still gets through a little, but not nearly enough that it would register as a logic-high state anywhere.
Yellow = MAX9926 output (no false triggers wanted here)
Green = Filtered input signal
Blue = Raw/pre-filter input signal
Note the voltage scales.
(http://www.e30tuner.com/assist/e36x/e36x008.png)
Zoomed in a bit more on the central spike.
(http://www.e30tuner.com/assist/e36x/e36x009.png)
I also lifted a wheel and played around to see how slow I could spin it and still trigger the MAX9926. It looks like ~6.7Hz, or ~0.6MPH. So...I think it is plenty sensitive.
(http://www.e30tuner.com/assist/e36x/e36x010.png)
Just for fun, here's a capture of me using my foot to give the wheel a big push and letting it coast to a stop again. I managed to get it going a whopping 7.4MPH! The Wavetrac diff did present a little bit of resistance to spinning one lifted wheel.
(http://www.e30tuner.com/assist/e36x/e36x011.png)
That's enough fooling around with this for now. At some point I will have more than oscilloscope shots to share lol. Well, it'll probably be Excel tables of wiring diagram pinouts and drawings of the harness before photos of anything actually interesting show up lol. Madness? This is NERD OCD!
-
I'm glad to have ran into this thread, I joined this forum yesterday, and I happen to be a motorsports electronics engineer.... and a Link dealer... and am converting my 318ti M44 to a standalone ECU in the next few weeks.
Comments on your thread:
1. You can get all those Mini Timer (we call them Bosch LK's) connectors and components from milspecwiring.com or racespeconline.com. Great resources for engine management system wiring supplies.
2. Based on your posts, if you can somehow return that E36X link, I would. Get yourself a Storm or Extreme instead, the hardware is the same but they have a lot more flexibility as they're not constrained to the BMW AMP connector on the ECU. You can find the headers with flying leads, or even buy complete adapter harnesses, in plenty of places. So its still plug & play, but more flexible. This is what I'll be doing, with adapters for several different ECUs.
3. When you're ready for knock sensing, get a Link KnockBlock or another knock audio amplifier with a 3.5mm audio out that you can connect to your computer.
4. Go fully sequential on fuel and I'd consider a coil on plug conversion to go fully sequential spark as well. I've just received the plate and coils to convert my M44.
5. Link has 2 fueling modes, "traditional" uses MAP as the primary load source; you may find the modeled fuel equation better. This uses MAP as well but creates an air charge estimate and then determines fuel mass to inject. It requires a bit more injector data but its ability to track the lambda target is excellent.
6. For traction control, throttle-based torque reductions are about NVH and emissions compliance. Torque reductions based on fuel reductions and ignition cuts are more incremental, responsive and effective.
7. The M50 IAC is a good one, so good in fact I use it everywhere. I have twin M50 IACs on 1400hp turbocharged offshore powerboat V8s. I used a pair on a Lamborghini LM002. We used them for active engine braking control on Suzuki Superbikes. Its the Swiss-army knife of air control valves.
8. I highly recommend adding a fuel pressure sensor from the beginning. It is the most common, #1 issue in engine management system installations, and doing it now will save you at very least an equivalent amount of time at some point later in your project.
10. And NOW FOR THE WHEELSPEED SENSOR discussion. Caveat #1: I'm not an EE, I'm a calibrator with an old and worn out brain. So please tolerate my muddling through the following:
All the Link ECU digital inputs are designed to read open collector 0-5V square waves. They are not variable reluctance like the crank and cam. They do have a software-selectable pull-up and you can define the edge. Problem is that most ABS sensors are VR, and worse, they have a pretty low output at low speeds because of the tooth counts involved, as you saw from your testing. I've used this unit: https://www.milspecwiring.com/DMC-D-Converter-Wheel-Speed_p_528.html
I haven't had luck piggybacking ABS signals an ECU speeds with a mag/hall convertor, and I don't know anyone who has. Standard practice is to get wheel speeds off of a CANBUS (which your ABS unit doesn't have) or to use an ABS unit that has open collector outputs. 2002 and later E46 ABS units are like this, and I know quite a few people who have retrofitted this to the E30 and E36 chassis with success. Honestly, this is the best way for you to get traction control & upgrade your abs in one shot. That said, it might be a fun experiment to see if you can share those signals between the stock ABS unit and get a reilable speed at the Link.
Feel free to ask any questions! As soon as I find a clean, complete DASC kit I'll be doing a standalone install myself.
Cheers,
Neel
-
I'm glad to have ran into this thread, I joined this forum yesterday, and I happen to be a motorsports electronics engineer.... and a Link dealer... and am converting my 318ti M44 to a standalone ECU in the next few weeks.
Comments on your thread:
1. You can get all those Mini Timer (we call them Bosch LK's) connectors and components from milspecwiring.com or racespeconline.com. Great resources for engine management system wiring supplies.
2. Based on your posts, if you can somehow return that E36X link, I would. Get yourself a Storm or Extreme instead, the hardware is the same but they have a lot more flexibility as they're not constrained to the BMW AMP connector on the ECU. You can find the headers with flying leads, or even buy complete adapter harnesses, in plenty of places. So its still plug & play, but more flexible. This is what I'll be doing, with adapters for several different ECUs.
3. When you're ready for knock sensing, get a Link KnockBlock or another knock audio amplifier with a 3.5mm audio out that you can connect to your computer.
4. Go fully sequential on fuel and I'd consider a coil on plug conversion to go fully sequential spark as well. I've just received the plate and coils to convert my M44.
5. Link has 2 fueling modes, "traditional" uses MAP as the primary load source; you may find the modeled fuel equation better. This uses MAP as well but creates an air charge estimate and then determines fuel mass to inject. It requires a bit more injector data but its ability to track the lambda target is excellent.
6. For traction control, throttle-based torque reductions are about NVH and emissions compliance. Torque reductions based on fuel reductions and ignition cuts are more incremental, responsive and effective.
7. The M50 IAC is a good one, so good in fact I use it everywhere. I have twin M50 IACs on 1400hp turbocharged offshore powerboat V8s. I used a pair on a Lamborghini LM002. We used them for active engine braking control on Suzuki Superbikes. Its the Swiss-army knife of air control valves.
8. I highly recommend adding a fuel pressure sensor from the beginning. It is the most common, #1 issue in engine management system installations, and doing it now will save you at very least an equivalent amount of time at some point later in your project.
10. And NOW FOR THE WHEELSPEED SENSOR discussion. Caveat #1: I'm not an EE, I'm a calibrator with an old and worn out brain. So please tolerate my muddling through the following:
All the Link ECU digital inputs are designed to read open collector 0-5V square waves. They are not variable reluctance like the crank and cam. They do have a software-selectable pull-up and you can define the edge. Problem is that most ABS sensors are VR, and worse, they have a pretty low output at low speeds because of the tooth counts involved, as you saw from your testing. I've used this unit: https://www.milspecwiring.com/DMC-D-Converter-Wheel-Speed_p_528.html
I haven't had luck piggybacking ABS signals an ECU speeds with a mag/hall convertor, and I don't know anyone who has. Standard practice is to get wheel speeds off of a CANBUS (which your ABS unit doesn't have) or to use an ABS unit that has open collector outputs. 2002 and later E46 ABS units are like this, and I know quite a few people who have retrofitted this to the E30 and E36 chassis with success. Honestly, this is the best way for you to get traction control & upgrade your abs in one shot. That said, it might be a fun experiment to see if you can share those signals between the stock ABS unit and get a reilable speed at the Link.
Feel free to ask any questions! As soon as I find a clean, complete DASC kit I'll be doing a standalone install myself.
Cheers,
Neel
Thanks for the detailed response, there's a lot of good feedback in there.
1. Good to know. I am always happy to find new sources for these things. Regarding wire harness materials, I will be able to keep together most of the existing wire in the stock harness, but will be replacing a few key conductors. Specifically, I am replacing the switched legs of the ignition coil primaries since the stock shielded wire setup is not up to "modern" standards...they stripped the shield back almost 5" where the wires go into the 88 pin plug, so the big EMI spikes from the inductive flyback on the primaries are unshielded where those wires are stuffed up against all the other signals. Obviously it works well enough, but I want to yank them and replace them, with shields terminated in the way specified in all of the newer BMW wiring diagrams ("shield extends up to <= 10mm from ends"). Right now, I have found very good pricing on shielded TEFZEL wire (MIL-DTL-27500/MIL-DTL-22759) at several aircraft wiring supply sites. I am 99% sure that I'll be going with "TG" series shielded TEFZEL wire for the new ignition lines since it is rated at 150degC and 600V, and has a braided copper shield which is probably even better than the lightly twisted shield in the stock wire. I'll be using 16ga (~1.5mm2) there. Since most places sell 100ft minimums, I am also going to use it for the switched legs for the injectors, ICV and evap purge valve (all the switched items). Necessary? No. But why not, if I have a spool of it. And at least for injectors & ignition, 16ga is a bit larger than the stock stuff anyway.
2. I am pretty locked-in to the E36X (which Link confirmed is an XtremeX main board mated to a Motronic-shaped carrier board that houses the IGBT coil drivers and whatnot). Since I am not all that concerned about the warranty, I do plan to solder jumper wires between various pins on the board-to-board header and the AMP connector, so that it all runs through one loom. I am also considering a remote MAP sensor so that I don't have to run a vacuum line from the ECU through the firewall. Anyway, I really want to maintain the stock form factor & connector. Emissions inspections don't involve looking at the ECU or anything, but the state of California is kind of crazy and I want to look as stock as possible if they ever decide to start looking there.
3. Good to know about knock calibration. I assume that getting it set up properly involves more than just plugging in the bore diameter and a windowing angle range? This is 100% new to me.
4. Yup, full sequential fuel is a requirement...no point in all this work if I don't take full advantage of it. Also, fun fact...I invented the M42/44 COP conversion, right here on M42Club back in ~2006. So, it is needless to say that I have already converted.
5. I plan to roll with the modeled fuel mode. Again...all this trouble for (likely) little power gain, so I am going to use every feature that I can. My plan is to machine an inline adapter that goes into the feed line to the fuel rail, and equip it with a Bosch PST-F1 (combined temperature & pressure sensor). I figure that I'll get a reasonably good read of pressure, and "close enough" on the temperature, with the sensor mounted ~12" from the rail. The other option would be to get a spare rail and try to mount it directly into there, but I don't know if that is necessary. Additionally, I plan to use the same sensor in place of the stock oil pressure switch so that I can monitor pressure & temperature, and have the ECU control the oil light in the instrument cluster. The only challenge is that the pressure switch hole is M12x1.5, and the sensor is M10x1, so to adapt the sensor it'll be offset out of the hole ~5mm by the adapter.
A tuner that I have worked with a lot recommended retaining the MAF sensor during tuning. Not that the ECU will use it, but using it as a source of additional telemetry (since the ECU does have spare ADC inputs) was suggested as a good way to start really getting a good feel for the VE/MAP readings as I tune stuff. Thoughts?
6. Good to know about TC methods...I'd like to not have to convert to E-throttle if possible. Programmable throttle curves seem fun, but it would be a tremendous amount of work.
7. Awesome to know that the M50 IAC is a solid performer. I have one on order.
8. See #5.
10. Regarding the wheel speed sensors, the custom board I design will basically be an actively driven TTL output setup. That is what the MAX9926 is all about. It is a chip designed specifically for interfacing with VR sensors and producing a TTL output. Personally, I don't like open collector arrangements in the car environment since the pull-up resistor makes for a high impedance signal line when the output is "off", and at least as far as I have seen so far, ignition EMI is not insignificant. So, I will be taking the MAX9926 open collector output and then buffering it with a fully active line driver, so that both high and low output states are actively driven / low impedance. As you can see above, the rough tests I did show that the MAX9926 will reliably pick up the wheel speed signal down to ~0.6MPH, which I assume is going to be fine. My interest in TC is much more about conditions when driving / cornering under high throttle, not so much to minimize wheel slip when accelerating from a stop. Besides, the ~200bhp I am making now combined with very sticky tires means that I can't do much spinning anyway lol. I will be happy to share what I do regarding VR signal adaptation since it looks like I have it all taken care of. The ABS computer does have its own IC that does a pretty good job of converting the VR sensor signals to TTL output, but I want to avoid hacking up the ABS computer at all since it is a critical safety system, and it also (basically) disables itself in the event of any fault condition, to the point that it drops the power rail to the VR signal conditioner IC. So, an external solution that directly reads the VR sensors seems like the way to go.
-
All good. I'm in Southern California, smog's going to be an issue. A circuit that will convert common ABS wheel speed sensor outputs to a 0-5V square wave without any effect of the operation of the ABS is something I wished I had multiple times.
-
All great info here.
Welcome to the forum Neel !! We can definitely trust what Neel brings to the table since I know of Neel and have heard only great things about him.
Neel... we have a mutual friend !!! Jimmy Pettinato. Neel did an amazing job with Jimmy's 2.3L S14. Jimmy is a really great friend of mine.
Welcome again!!
Cheers,
~Ralph
-
Ralph, thanks for the kind words. Jimmy is a good friend and I look forward to when I can see him and his stable of E30's myself!
The funny thing is I am here as a "civilian." Though I've been a tuner for 20 yerars, I've never tuned my own car. So its time to put my money where my mouth is. Guess I'll be taking my work home with me!
All great info here.
Welcome to the forum Neel !! We can definitely trust what Neel brings to the table since I know of Neel and have heard only great things about him.
Neel... we have a mutual friend !!! Jimmy Pettinato. Neel did an amazing job with Jimmy's 2.3L S14. Jimmy is a really great friend of mine.
Welcome again!!
Cheers,
~Ralph
-
Ha, small world it seems! At least it is for lovers of old German cars.
Do you have a recommendation for a type or source for splices? I'd like to find a small/compact butt splice with heat shrink tubing for some areas of the harness where BMW used an existing splice but a lot of extra wire looped in (which I'd remove) for ease of assembly. For a case like where a bunch of wires join (like where most of the ECU ground all tie together with one larger conductor that goes to the ground lug, what's a good sleeve type to use?
-
Ha, small world it seems! At least it is for lovers of old German cars.
Yes it is, and one more thing: Jimmy's car also runs a Link ECU, so there's another resources for this thread.
Do you have a recommendation for a type or source for splices? I'd like to find a small/compact butt splice with heat shrink tubing for some areas of the harness where BMW used an existing splice but a lot of extra wire looped in (which I'd remove) for ease of assembly. For a case like where a bunch of wires join (like where most of the ECU ground all tie together with one larger conductor that goes to the ground lug, what's a good sleeve type to use?
See here:
https://www.milspecwiring.com/search.asp?keyword=splice&search=GO (https://www.milspecwiring.com/search.asp?keyword=splice&search=GO)
The more expensive Raychem ones come with shrink, the less expensive barrel splices you should cover with a piece of semi-rigid glue shrink:
https://www.milspecwiring.com/W5-Glueline_c_450.html (https://www.milspecwiring.com/W5-Glueline_c_450.html)
I don't find a need to use the Raychem species except where weight and compactness is the #1 priority; in practice I feel both work the same.
Cheers,
Neel
-
Thanks! "Parallel splice" is what I was looking for it seems.
Question...I have seen some places mention that MAP sensors (and oil pressure) should not be mounted on the engine itself as the vibrations will cause premature failure. Other places make no mention of this. What is your thought on it? In my case, I am running stock M42 hydraulic mounts, and I plan to continue to do so. The oil filter housing already has a perfect threaded boss for the Bosch PST-F1, and I am 99% sure that I am going to use a Bosch PST-1 mounted on the intake manifold plenum since that gets me MAP+IAT, and I don't have to mess with a vacuum line to the ECU. Also, it looks like the Bosch KS4 knock sensors are cheap and readily available, so I will be getting some of those too.
PST-1 data: https://www.bosch-motorsport.com/content/downloads/Raceparts/Resources/pdf/Data%20sheet_70513419_Pressure_Sensor_Combined_PST_1/PST_3.pdf
PST-F1 data: https://www.bosch-motorsport.com/content/downloads/Raceparts/Resources/pdf/Data%20Sheet_70496907_Pressure_Sensor_Combined_PST-F_1.pdf
KS4-P data: https://www.bosch-motorsport.com/content/downloads/Raceparts/Resources/pdf/Data%20sheet_69010059_Knock_Sensor_KS4-P.pdf
-
Question...I have seen some places mention that MAP sensors (and oil pressure) should not be mounted on the engine itself as the vibrations will cause premature failure. Other places make no mention of this. What is your thought on it?
Like so many things its on a spectrum, the answer is if you can remove mount the sensors you they will last longer. The more high-frequency vibrations your motor has, the worse its going to be. I've had customers direct mount them and they are fine. We hard mounted them to some Rousch v8's in early Grand-Am days, they wouldn't last a race that way.
Bosch motorsports sensors are great, for your application just find their OEM application. 0261230030 1 bar TMAP is used on all sorts and will work great.
The PST-F1 is just a Mazda CX9 part.
That KS4 is super, super common. Just google it.
I can't comment on whether the ones bought directly from Bosch Motorsports are in some way superior, but in my experience the OEM sourced ones have never failed me. And its really, really hard to mess up something like a KS4. If I was running a pro-racing team, I'd buy them from Bosch Motorsports for the peace of mind. On my car? I'd find the cheapest alternate supplier version - not to save money, just to see for myself if there's any difference in performance or longevity.
-
I have been been a little quiet in here lately, but I have been working on this more. Specifically, I have been drawing up the fully detailed wiring diagram for the new harness and a pin-board to get length estimates with. Although I do not plan to make a physical pin-board since enough of the original harness will remain intact to keep things properly sized, I will probably install it into the chassis after removing all of the tape and cleaning it so that I can route all of the new stuff in-place to get the lengths exactly right. The pin-board drawing is more for determining quantities of wire to buy.
PDF links are the full-size drawings of the "thumbnail" images.
For the pin-board drawing, I started out by measuring out everything on a 100% stock harness. Dimensions probably vary a bit since these things are all 30 years old and varying amounts of tugging/abuse have been applied, but everything is likely within 1cm of where it should be.
OEM E30 M42 Harness Dimensions
http://www.e30tuner.com/assist/e36x/PinBoard-OEM.pdf
(http://www.e30tuner.com/assist/e36x/PinBoard-OEM.png)
I have already posted this elsewhere, but here are the OEM E30 M42 wiring diagram and the modified one I am using currently with my MAF conversion & WBO2 on stock Motronic, in full color:
http://www.e30tuner.com/assist/m42wireharness/EngineHarness_M42B18_E30_318iS_OEM.pdf
http://www.e30tuner.com/assist/m42wireharness/EngineHarness_MM2100.pdf
Anyway, it took a fair bit of work to figure out exactly how I wanted to add & route all of the new stuff for the Link ECU. A primary goal was to have a single wire loom coming from the ECU, which means that I will need to void my warranty and solder some jumper wires inside the thing from the "extra" I/O pins on the G4X ECU and unused pins on the main 88 pin connector. Also, while it has a built-in MAP sensor, I do not want to have a vacuum line running through the firewall (both from a SMOG/visual standpoint, and just for cleanliness). So that means that I will be using a Bosch MAP+IAT sensor, mounted directly in the plenum of the intake manifold.
The other thing I had to think about a lot was the fuel injector wiring. The stock setup has a pluggable sub-harness for the injectors. The ONLY reason I can see for this is to make engine removal/installation simpler at the factory. Removing the injector harness requires removal of the upper intake manifold. In my experience, the M42 is much more easily removed/installed without the upper manifold anyway, and (*FINGERS CROSSED*) I don't anticipate removing the engine again anytime soon. With the "mess under the intake" mod, the upper manifold can be removed without messing with the TB, and is a 10 minute job. So, with that said, the fuel injector wiring will run through the little side-port in the rubber umbilical that the ICV wires previously exited from. This is the most direct route for the injectors. The ICV, MAP & fuel P&T sensor wiring will exit where the fuel injector connector used to be (with a 3D printed PEEK filler/adapter for the grommet). It just makes more sense that way.
New stuff which I will be routing through the wire box under the intake manifold:
- Oil pressure + temperature (mounted in oil filter housing where the pressure switch was, with some custom machining to adapt the existing M12x1.5 hole to take the M10x1 sensor)
- Fuel pressure + temperature (will machine an inline tee adapter for the fuel feed line)
- Manifold pressure + temperature (no long vacuum lines to mess with, and nice direct measurements in the plenum)
- Dual knock sensors (mounted to the existing knock sensor bosses on the block)
- M50 ICV (still not quite sure where or how I will mount it...it is a fair bit longer than the M42 ICV and has larger in/outlet ports)
As previously mentioned, I will be adding 4 wheel speed inputs. On top of that, I will be adding connections to the brake switch, and adding a clutch switch. The ECU supports "flat shifting" and since that only requires one additional wire to be run from the clutch switch, why not? If I am going to expend all of this effort, then I am going to take advantage of every possible feature. The only thing I do NOT plan to do is convert to electronic throttle...that is just way too much work for minimal gain in anything, at least for now.
That is a lot of typing. Here are the drawings of the new & improved pin-board & wire diagrams. These are certainly a bit busier than the OEM ones! I shudder to think about what these would look like on a modern BMW engine.
http://www.e30tuner.com/assist/e36x/PinBoard-E36X-Prelim.pdf
http://www.e30tuner.com/assist/e36x/EngineHarness_E36X-Prelim.pdf
(http://www.e30tuner.com/assist/e36x/PinBoard-E36X-Prelim.png)
(http://www.e30tuner.com/assist/e36x/EngineHarness_E36X-Prelim.png)
If you are thinking "damn, this guy has a bit of OCD...he's only making one of these" then you are at least partially correct. Regardless of whether or not I actually have OCD, graphic design has always been a little side passion of mine, although I am really mostly into technical drawings rather than "art." More than that though, I have found that with wiring projects, the Seven P's of Life apply very heavily. Proper Prior Planning Prevents Piss Poor Performance. When I was younger and far less patient, wiring/electrical work was done much more ad-hoc and always ended up messy, buggy and ultimately causing many headaches. At least for me, fully documenting & detailing a project like this means that the experience will be a lot more enjoyable and likely to work on the first try. And of course, my E30 brethren might find this useful. If documenting some of this work inspires someone else to do this (or something similar) then it is all worth it.
Anyway, I got the drawings done enough today that I can finish my list of materials and start ordering wire, connectors and other supplies. The next big task will be to completely tear-down the spare donor harness and clean it up. There is an unreasonable amount of "goo" all over it from the decaying harness tape, which will probably require me to go through at least 500mL of isopropyl alcohol. I have already been through this once when fully rebuilding/modding the harness that is in the car now, and it is a pretty tedious task!
Can you guys recommend some sources of good molded hoses? I will need some 90 degree elbows and whatnot, probably with a pretty tight radius, to make the M50 ICV work. I'll also need some reducers and other things like that. The M5x vacuum hoses for the ICV might work if I hack them up, but they seem to be needlessly expensive.
Lastly, what are your thoughts on the following. The opening in the rubber umbilical guide where the ICV wire exits is sized for a ~4.5mm OD wire sheath. In order to run the 5x16ga wires for fully sequential injection, I need to use a sheath that is ~9mm OD. I have test-fitted this, and physically I can get it to run through there. However, I have some concern that over time the rubber may split open, being stretched to ~2X its original circumference. Information I have found online indicates that vulcanized rubber can be stretched to well past 3X its original length without issues, but if anyone here happens to know a lot about rubber compounds I'd appreciate thoughts on whether I should reconsider this. It really is the ideal spot to route the injector wiring through!
-
Question...I have seen some places mention that MAP sensors (and oil pressure) should not be mounted on the engine itself as the vibrations will cause premature failure. Other places make no mention of this. What is your thought on it?
Like so many things its on a spectrum, the answer is if you can remove mount the sensors you they will last longer. The more high-frequency vibrations your motor has, the worse its going to be. I've had customers direct mount them and they are fine. We hard mounted them to some Rousch v8's in early Grand-Am days, they wouldn't last a race that way.
Bosch motorsports sensors are great, for your application just find their OEM application. 0261230030 1 bar TMAP is used on all sorts and will work great.
The PST-F1 is just a Mazda CX9 part.
That KS4 is super, super common. Just google it.
I can't comment on whether the ones bought directly from Bosch Motorsports are in some way superior, but in my experience the OEM sourced ones have never failed me. And its really, really hard to mess up something like a KS4. If I was running a pro-racing team, I'd buy them from Bosch Motorsports for the peace of mind. On my car? I'd find the cheapest alternate supplier version - not to save money, just to see for myself if there's any difference in performance or longevity.
Great info, thanks. Do you have a PN for the CX9 oil P+T sensor? I can't seem to find it.
I am going to take my chances with mounting the oil & MAP sensors onto the engine. Again, it is on stock hydraulic mounts and will not be operated in an excessively harsh setting, so I figure it is at least worth a shot. Only the MAP sensor would really be a big problem if it crapped out, and it looks like it was designed to be installed in a manifold anyway.
-
Come to think of it the Mazda ones are for boosted applications. But there's another Bosch one used on a lot of bikes that would be perfect:
https://www.ebay.com/itm/Bosch-1-Bar-TMap-Manifold-Absolute-Pressure-Sensor-with-IAT/264607384540?epid=1323920385&hash=item3d9bd443dc:g:gHsAAOSwoPJeJ-8E
-
I spent a number of hours yesterday tearing-down my spare harness and cleaning it. It took nearly a pint of 99% isopropyl alcohol to get the tape residue and grime off of all of the wires. If you have ever worked on one of these old harnesses, you know the pain of dealing with that nasty tape adhesive! It was a task that I had not been looking forward to one bit, since I had done it once before at the start of 2020 when I cleaned up and modded the harness that is in the car now (integrated MAF & WBO2 wiring, properly routed/trimmed ignition coil leads: all for the stock ECU). This time was a little easier since I COMPLETELY took the harness apart...I completely de-pinned the ECU plug & relay sockets, chopped off all of the JPT plugs for the various sensors & actuators and permanently removed all but 5 terminals from the diagnostic plug (leaving only the ones needed for SI light reset & the tach signal). Most of the wire sheaths were removed, with only the little pieces near C101 and the diagnostic plug are going to remain. The sheaths on the main power & ground wires will be removed when I chop apart the splices, since I need to add / change wires in those bundles. My pile of "scrap" harness wires is as large as what remains! I took some pictures, but they are at home on my camera, so I'll see about posting some of those up later today.
As of last Thursday, my big order for new wire, parallel splices, heat shrink tubing & new PVC sheathing have shipped, so I should have a big pile of new stuff to start roughing-in this week. A big beef I have had with the harnesses is that a lot of wires are all tangled & twisted. This is why I completely took the harness apart...all wires will be bundled a LOT more neatly, with no needless weaving/twisting, no loop-backs and more than a dozen splices completely removed. Every signal / analog wire that ran from the ECU to the wire box has been removed since they all had little splices on them in the wire box. This was done to make harness assembly easier...pig-tails from each connector were made, routed in to the box and then joined to the long wire from the ECU, rather than running a single wire and having to assemble the connectors onto the ends at the end. Also, I chopped off all of the connectors (except for the crank & cam position sensor ones, those are fine the way they are) because they were heat-staked to prevent terminal removal. You can actually release the terminals if you knock out the little staked sections with a hobby knife, but that leaves openings in them right at the edge of the boot. Maybe I will take some pictures of this, just in case anyone is interested.
Other than roughing-in the wires, not much else will be done until I can yank out the existing harness and put this disassembled one into the car. I am going to size & route all of the new wires in-place before installing any connectors, tape or other fixings. A big pet peeve I have is that all of these are "too long" inside the car where the main loom runs to the ECU. I'd guesstimate that they are close to 10cm too long, requiring a bunch of bending & brute force to cram the wires out of the way to get the ECU plug into place. As it is, 75% of the wires going to/from the ECU have been removed and new wires+terminals have to be installed, so I will chop the terminals off of the remaining wires and cut them to a proper length once I have it all dry-fitted in the car.
More to come.....
-
Here's a picture of what remains of the original harness that will be used going forward...
(http://www.e30tuner.com/assist/e36x/e36x011.jpg)
...and here is what is being discarded. Well, most of it. I am keeping the relay sockets, which were removed for cleaning & wire re-routing.
(http://www.e30tuner.com/assist/e36x/e36x012.jpg)
Part of me was tempted to just build a whole new harness from scratch, but that would have ended up being a few hundred dollars in needless extra cost. The stock wire has PVC insulation as far as I can tell, which is not amazing or anything, but it is perfectly fine for an engine harness. The new wire I have ordered all has Tefzel (ETFE) insulation, which is considerably sturdier while also allowing for thinner wall thickness. Smaller overall wire diameter makes for slightly easier routing, and since I am going to be increasing the number of wires coming from the ECU plug by 28, I want to have some extra help in being able to fit them all out of there!
-
Today I started in on some CAD for adapting the Bosch pressure/temperature sensors to fit on the engine. The one for the oil will go in the oil filter housing where the stock pressure switch was. Since the existing hole is M12x1.5, and the sensor is M10x1, I need to drill it out a bit larger and install a thread repair sleeve. It is also a bit longer than I'd like since (ideally) the thermistor tip in the sensor would be in the actual flow of oil. I can't trim it enough to get the sensor that far in, but I can certainly get it a bit closer. I got out the calipers and made some measurements with which I modeled the threaded boss area. The main limiting factor for pushing the sensor further in is the big open cavity inside where the oil bypass valve is (the one that should never open unless somehow the filter gets totally clogged).
(http://www.e30tuner.com/assist/e36x/e36x012.png)
So with a little trimming that can all be done pretty easily on a manual mill, here's how the sensor will end up fitting in there.
(http://www.e30tuner.com/assist/e36x/e36x013.png)
(http://www.e30tuner.com/assist/e36x/e36x014.png)
For the fuel sensor, I am planning to have a little inline tee fitting CNC machined from some 7075 aluminum rectangular bar stock I have laying around. This will install into the 8mm ID hose that feeds fuel into the rail, as close to the rail as I can get it. I'd expect the fuel to heat up minimally overall since it flows at a fairly high rate and has a lot of metal tubing to dump heat from between the front & rear of the car, and it probably does not spend enough time in the rail to significantly heat up much more after the sensor, so I figure I will get a decent reading of it like this. The other option was to get a spare fuel rail and have a friend TIG a little threaded boss onto it, but that seems very unnecessary, and would be a pain in the butt to access if I needed to replace the sensor.
(http://www.e30tuner.com/assist/e36x/e36x015.png)
(http://www.e30tuner.com/assist/e36x/e36x016.png)
The other open items I have are to figure out where & how to mount the M50 ICV, and how to mount the MAP+IAT sensor. I'd like to fit the ICV in approximately the same location as the original, but it is pretty tight and will likely require even more custom machining. The other option is to mount it vertically in the open(ish) area behind the intake boot and a little to the left of the intake manifold. For the MAP+IAT, I am thinking I am going to mount it on the rear-most sloped face on the top of the intake manifold since that is the only spot I where I am confident that it'll clear the hood insulation. Maybe I will try sticking some foam blocks on the top flat part to see if I can clear the insulation closer to the middle, but it seems iffy. Either way, it needs 9~10mm of material thickness to get a seal with the o-ring it uses, so I will need to machine a little mount plate or flanged sleeve or something.
-
I started doing some basic routing and roughing-in of new wire runs today. There are still a number of items and some of the heavier gauge shielded cable which I am waiting to receive, but I can get a lot of stuff into place while I wait. The plan is to just get the wires in there, but I will not be crimping/splicing/taping anything at all until I can get this fitted into the car. Once I do that, then I can make the final decisions about lengths of things and begin making permanent crimps. I also want to see how things actually end up being positioned, specifically some of the big parallel splice bundles. The big one with all of the switched 12V outputs from the main & fuel pump relays needs to have one of its smaller wires replaced with a longer run, so I either need to cut the existing splice off and make a new one with the longer wire, or just make a butt connection to extend it. The latter is far easier, but the former is cleaner. I only really pause thinking about this because the exposed copper strands from that splice are all greenish, and if the oxidation extends too far up into the wires then I might have to trim off a lot more than I want (or attack them with some fine sandpaper). Overall this is just me having fun over-thinking things, which I am sure you have figured out by now!
Here's what the big wire box looks like with new runs pulled through to it. The existing wires were fine, but they all had those obnoxious splices + rubber caps which ate up almost 50% of the available volume. I understand why they did it that way, to make mass production easier, but I don't want to have to deal with the mess. There are some other splices like that in other places in the harness which I am also removing.
(http://www.e30tuner.com/assist/e36x/e36x013.jpg)
Here's where I left things today. I am going to take it easy and spend the evening relaxing and enjoying the last few hours of 2020. It's been a rough year in a lot of ways, so I can't say I will miss it too much!
(http://www.e30tuner.com/assist/e36x/e36x014.jpg)
-
More progress...
I finished designing a small PCB to condition the 4 wheel speed sensors' signals. It measures 32x32mm, with most of that size being driven by the wire-to-board terminal blocks. I'll 3D print a small enclosure to secure the board & wires, which will be mounted up near the knee bolster inside the dash next to the ABS computer. These little boards are in production now, and I expect to have them in a week or so. The minimum order quantity is 5, so I will have some extras that I can sell (bare board, or assembled) if anyone with a stand-alone ECU wants a quad-VR conditioner board.
(http://www.e30tuner.com/assist/e36x/e36x017.png) (http://www.e30tuner.com/assist/e36x/e36x018.png)
Other than that, I have not done too much since the last post since I am waiting on the last of the shielded cable & some connectors to arrive.
-
Today's updates...
I finally found a cheap crimp tool that works really well with the 2.5mm (unsealed) terminals. It is not really ideal for the JPT and SPT type terminals where the insulation grips are parallel and supposed to crimp into an "M" shape, but they are fantastic for ones like this with staggered insulation grips. They are low-leverage ones, and the crimps take 2 operations, but that is fine since I do not need to do too many of these.
Crimpers: https://www.bmotorsports.com/shop/product_info.php/cPath/111_112_170/products_id/364
Here is how my new wire runs for C101 wound up (oil pressure light will now be controlled by the ECU, and I ran a new coolant gauge sender wire to eliminate the splice in the wire box). It is not production quality, but it is plenty good for this.
(http://www.e30tuner.com/assist/e36x/e36x015.jpg)
Here is what the crimps look like with the "wrong" tool.
(http://www.e30tuner.com/assist/e36x/e36x016.jpg)
Next, I played around a bit with different methods of shield termination. The factory wiring strips the cable sheath back a number of inches, twists the exposed shielding into a bundle, sticks plastic tubing over it and then crimps all of them together with a grounding wire outside of the DME connector housing. I have never liked that arrangement, since all of the sensitive sensor lines are packed right in there next to the unshielded lengths of ignition lines and stuff. So, I decided to see how compact of a termination I could make really close to the end at the DME terminals. It looks like I can get within a few millimeters.
(top) A parallel crimp is the simplest way to go, but it is just too bulky once you put heat shrink over it.
(middle) Stripping the sheath off and soldering a ground run is very compact, but it leaves jagged soldered edges poking against the central conductor's insulation which could poke through. No good.
(bottom) Stripping the sheath and folding the shield braid back, and THEN soldering the ground termination made the cleanest arrangement. It is only marginally larger than the middle setup, and it is what I plan to go with.
(http://www.e30tuner.com/assist/e36x/e36x017.jpg)
Here's how I will be doing all of the shields. First, strip 10mm of outer sheath off. Then bend the shield braid back over the outer sheath and trim it down to 5mm.
(http://www.e30tuner.com/assist/e36x/e36x018.jpg)
Next, get your ground termination wire and strip enough insulation so that you can wrap the conductor around the folded shield 2-3 times (2 seems like enough). Separate 4-5 strands for the lashing, and trim the other ones down to ~5mm.
(http://www.e30tuner.com/assist/e36x/e36x019.jpg)
Tightly bind the ground wire onto the shielded area. TIGHT! Also make sure that none of the strands (shield or ground) are poking up or out. It should all be nice and smooth.
(http://www.e30tuner.com/assist/e36x/e36x020.jpg)
Solder it all together. Don't use too much; you do not want blobs or bulges. Just use enough to wet everything. Normally, I say that solder has NO place in an automotive wire harness, and I generally abide by that. I’d certainly never use solder to splice conductors together or attach a terminal, but shield terminations are a bit different in many ways. Also, sometimes space constraints demand it, and all of these joints will be inside the cabin where temperatures and the elements won't be a factor nearly as much as under the hood. Additionally, I will be cleaning all of these with alcohol to remove as much of the flux as possible (flux will slowly attack the wire and insulation, although it would probably take decades to actually be any kind of an issue).
(http://www.e30tuner.com/assist/e36x/e36x021.jpg)
For those who are interested, here is NASA's guidance for workmanship standards in wire harnesses (or some of it at least). Being that NASA sends ships to space, and I am working on God’s Chariot which will fly majestically in the heavens, it makes sense to draw from their expertise.
https://workmanship.nasa.gov/lib/insp/2%20books/links/sections/407%20Splices.html
https://workmanship.nasa.gov/lib/insp/2%20books/links/sections/210%20Shield%20Crimps.html
https://workmanship.nasa.gov/lib/insp/2%20books/links/sections/401%20General%20Requirements.html
I roughed-in a little more of the wiring as well, specifically for the fuel injectors which will be controlled fully sequentially. The wiring for them now runs through the opening where the ICV wires used to come out. It is the most direct route, and it allows me to salvage the 2.5mm2 red/white wire that comes out of the fuel pump relay to power them (it is long enough to reach the injector wire box via this route, but not long enough to go down into the main wire box and then back up).
(http://www.e30tuner.com/assist/e36x/e36x022.jpg)
It was a chore to stuff this 8mm sheath through the opening which was designed for a 4mm sheath. I am hoping that this will not lead to an issue in the future, like splitting open. From the technical info I can find online, it sounds like vulcanized rubber can easily stretch to 5-10x its original length and not creep or suffer other issues. I didn't take pictures of how I got it in there, but it involved folding an end length-wise, stuffing it in about an inch, forcing as many wires into the un-folded side as possible and then pulling that part through with pliers to get it in there at full diameter. Also, Windex makes for a great lubricant...very slippery, not really harmful to anything and it dries fast!
(http://www.e30tuner.com/assist/e36x/e36x023.jpg)
I also replaced the rotten shrink tubing on most of the lugs. For the big ones, I used some 4:1 ATUM shrink...you can use a size large enough to slip over the lug, and it'll still cinch down onto the wire when heated. Most shrink tubing is 2:1 ratio, but if you look around online you can find the higher ratio stuff (I bought a lot of my wire and materials at prowireusa.com).
(http://www.e30tuner.com/assist/e36x/e36x024.jpg)
My new favorite type of splice is the parallel splice. They are much more compact than butt splices, and I really like that the working conductors are in direct contact with each other (they overlap inside the sleeve). I needed a longer wire run for the ICV since the fuel injector wires now occupy its old exit point, and the ICV power wire will now go down through the main wire box. Although I swore I would not have any splices in the harness at the beginning, splicing on some more red-white wire from an old scrap harness was just a much more practical solution than chopping off the existing parallel splice holding the bundle of red/white wires together. Although I have plenty of large parallel crimp sleeves, the factory crimps are really nice, and most of the copper wires are pretty heavily oxidized at this point, even many inches under the insulation. It would be a chore to clean up all of the wires to get a quality connection with a new splice, so just doing it for one little wire was the way to go.
(http://www.e30tuner.com/assist/e36x/e36x026.jpg)
Here's what the splice looks like before covering it up. A very good parallel splice crimper which is also very economical is in the link below. It is the one I am using.
https://www.parts-express.com/pro-crimp-tool-for-non-insulated-terminals-18-6-awg--360-644
(http://www.e30tuner.com/assist/e36x/e36x025.jpg)
Also, I received a bunch of goodies today! For some reason, knock sensors are a lot bigger than I thought they would be. That reminds me of some British humo(u)r...
https://www.youtube.com/watch?v=yHLZ4Rz2Kgk
(http://www.e30tuner.com/assist/e36x/e36x027.jpg)
-
I had a chance to play around today and start figuring out where things would go and how they would fit. First, I used a 3D print of the MAP sensor and connector (Bosch provides 3D models thankfully) to see if I could clear the hood insulation with it mounted on top of the intake plenum. My preferred location would have been the flat-ish area right beyond the throttle body, but there just is not enough clearance there and I don't want to chop out the insulation (although that would probably be the simplest solution. The next best place seemed to be on top, more or less aligned with the runner for cylinder 3.
To check clearance, I taped my cheap USB "endoscope" camera in various places and looked at how things fit with the hood closed. You can get these cameras on Amazon for like $20. They are sort of useless for checking inside cylinders and stuff since you can't control the articulation, but they come in handy in a lot of other places.
(http://www.e30tuner.com/assist/e36x/e36x028.jpg)
Here's the clearance with the sensor sitting on top of the cosmetic rib things on the plenum. I am going to machine a depression there to give this thing a nice flat surface to sit on, and to install a little sleeve thing to allow the o-ring on the sensor to seal (I removed the thermistor & inlet portion of the sensor that stick out the bottom before printing).
(http://www.e30tuner.com/assist/e36x/e36x029.jpg)
To gauge how much clearance I actually had, I adjusted a piece of tape until it just touched the insulation. With the MAT sensor there, I have 3mm of clearance at the tallest part. I expect to gain another ~1.5mm when I machine down the ribs.
(http://www.e30tuner.com/assist/e36x/e36x030.jpg)
I investigated M50 ICV placement a bit more as well. It looks like I can keep it in the same location (roughly) as the stock one, with a little modification to the stock metal bracket and a small machined part that allows that bracket to move up ~7mm and toward the rear by ~20mm based on eyeball measurements when holding stuff in place. I couldn't get any pics, but once I 3D print some test parts I can show you what I mean.
The other main thing that I started looking into, and determined that I have a problem with, is the front knock sensor. If you have never handled one before (like me), they are a lot bigger than you might think. Additionally, the ones I bought are even larger because they have the 2-pole plug molded into them, at a slight upward angle. The stock ones have the same size body, but no giant plug (or receptacle that needs to also fit onto it). Here's the existing boss where the front knock sensor goes. Thanks to the engine mount arm, water pipe, alternator mount bracket and oil pressure switch, it is pretty crowded in the area.
(http://www.e30tuner.com/assist/e36x/e36x031.jpg)
The only remotely plausible way to get the sensor + plug + boot in there is to position it like this. It is not jammed against either of the brackets, but there is at best 0.5mm of wiggle room. If I skipped the rubber boot and just used some wire seals instead, I think that it would likely be OK, but I really would prefer not to skip the boot since I have to tie the cable's shield to one of the terminals and don't want it exposed.
(http://www.e30tuner.com/assist/e36x/e36x032.jpg)
Furthermore, the oil pressure + temperature sensor is fairly large thanks to its connector, and since I am going to skip machining the oil filter housing and just use an M12 to M10 adapter fitting, the sensor will stick out even further than the pressure switch. Boot or no-boot, I don't think that the knock sensor can go here.
(http://www.e30tuner.com/assist/e36x/e36x033.jpg)
If I wanted to have the right amount of clearance for it, it would need to point this way, and the oil sensor could not possibly go here.
(http://www.e30tuner.com/assist/e36x/e36x034.jpg)
So that brings me to a decision between 2 options.
Option 1) Install the oil sensor in the back of the head where there is an M12 plug which I think (still not sure, trying to confirm) is for the head's main oil gallery. There is enough room between the head and firewall that the sensor, adapter and connector will fit fairly well. This way, I can keep the knock sensors I have and use them.
Option 2) Put the oil sensor in the oil filter housing, but get stock M42 knock sensors. I assume that the sensors themselves are either approximately the same as the ones I have, or at the very least tuned approximately right to work with my bore size (87.5mm, vs 84mm stock). The stock sensors are a lot more compact since they just mold the wire in and have the connector at the end of the small harness (same connector as the sensors I have too). In fact, the Bosch branded stock ones are a little cheaper than the KS4P sensors I already have, which is a big plus. I am 99% sure that these will enable everything to fit in there, with the only drawbacks being that the integrated harnesses will make things a little cluttered and these will probably become NLA at some point.
(http://www.e30tuner.com/assist/e36x/e36x035.jpg)
That's it for today. Progress is going to be a little slow as I make measurements and finalize positioning for things, but at least it all looks fairly plausible at this point.
-
I got a little more done today, this time focusing on the ICV and how to mount it. Thankfully it does look like I can position it behind the intake manifold like the original one, although it is a tight fit!
Here is how it will sit (solid) relative to where the stock bracket holds the ICV (transparent).
(http://www.e30tuner.com/assist/e36x/e36x020.png)
This is how the new one will look compared to stock.
(http://www.e30tuner.com/assist/e36x/e36x019.png)
It is a part that can pretty easily be laser cut from some 3/32" (2.4mm) mild steel sheet and then bent in a vise.
(http://www.e30tuner.com/assist/e36x/e36x021.png)
As far as being sure that it works, I 3D printed a number of test parts to hold the M50 ICV. Looking at the M42 and M50 ICVs side by side, you can see how much longer the M50 one is.
(http://www.e30tuner.com/assist/e36x/e36x042.jpg)
It took a few tries to get things exactly where I wanted them.
(http://www.e30tuner.com/assist/e36x/e36x043.jpg)
Here's the final 3D printed test bracket assembled onto the ICV and grommet.
(http://www.e30tuner.com/assist/e36x/e36x041.jpg)
You can see that it is a TIGHT fit back there, but there is enough clearance everywhere. This thing sort of nests into the manifold runners a little, but there are 3-5mm of space all around. I have no idea how awful it will be to get the lower hose on there, but I guess I will find out. Selecting hoses and adapters is the next thing I need to look into, but now that it is in place I can narrow things down a little.
(http://www.e30tuner.com/assist/e36x/e36x036.jpg)
(http://www.e30tuner.com/assist/e36x/e36x037.jpg)
(http://www.e30tuner.com/assist/e36x/e36x038.jpg)
(http://www.e30tuner.com/assist/e36x/e36x039.jpg)
(http://www.e30tuner.com/assist/e36x/e36x040.jpg)
-
when I mounted the m42 ICV using the silicone hose and removing the heater plate, inverted the mounting point for the ICV. I am going to look for a picture of it.
-
Here is the pic from when I delete the mess under the intake delete in 2011.
(https://live.staticflickr.com/65535/50836201928_618eb2d6df_c.jpg) (https://flic.kr/p/2ksdPJ9)IMG_8814 (https://flic.kr/p/2ksdPJ9)
-
Which part of the mount did you invert?
-
I can't recall exactly but I believe it is the bracket that attaches to the intake, or maybe I bent it to allow the ICV to sit better with the hose coming in from a new direction. It was over 10 years ago. I am currently out of town but if you need me to confirm, I can do so Tuesday.
-
Yeah, I'd believe that maybe you needed to bend it a little. I think I have it all figured out now with all of the 3D printed brackets, so we'll see how things go.
-
I got the stock M42 knock sensors today and did a quick fit check. These are definitely going to fit better, and I can keep the oil sensor in the filter housing.
Here is how a stock one fits with the wire exiting toward the rear, which is how I think I want it to go so that I can install the receptacle in the bottom of the wire box and have the sensors plug right in. Even with the other stuff in place, it is not interfering.
(http://www.e30tuner.com/assist/e36x/e36x044.jpg)
Here's how it looks with everything out of the way.
(http://www.e30tuner.com/assist/e36x/e36x045.jpg)
I could also turn it around and have the wire come out the front, so I have that as an option if necessary.
(http://www.e30tuner.com/assist/e36x/e36x046.jpg)
Here is a comparison between the M42 stock sensors and the KS4P sensors I had initially wanted to use. The stock ones are actually slightly larger, but having the integrated wire makes it a lot shorter overall.
(http://www.e30tuner.com/assist/e36x/e36x047.jpg)
(http://www.e30tuner.com/assist/e36x/e36x048.jpg)
Also, I put together one of my little wheel speed sensor boards. Unfortunately, I mixed up the footprint for the 5V regulator and fried it instantly lol (you can see the little burn spot where the magic smoke escaped). I corrected the issue and ordered a new set of boards. After removing the regulator and just powering the thing directly with a 5V supply, I was able to verify that one of the conditioner chips was working correctly, but the other one got cooked. Oh well, live and learn, and double check the datasheet!
(http://www.e30tuner.com/assist/e36x/e36x049.jpg)
-
Today I sucked it up and made a little bit of an oily mess to test fit the PST-F1 and make sure that it would clear the knock sensor. At first I tried to eyeball the fit, and came up thinking "oh sh*t" when it looked questionable lol. So, I removed the oil pressure switch, tried to control the oil drainage (I'd guesstimate that ~6oz came out before the "clean" side of the housing emptied out) and installed the sensor. It was close, but it clears the knock sensor with the connector and boot.
I don't entirely like how far out of the oil flow the thermistor tip is when using the thread adapter. It is probably 35-40mm away from where oil flows, and that's a lot of stagnant oil. Now, the housing is aluminum and conducts heat well, and has the full volume of oil flowing through it constantly, so I think that it should heat up to full temperature pretty well, but the response will probably be a little slow and I worry that it will cool off at highway speeds. I have a spare housing that I was thinking of machining to allow the sensor to be 10-15mm closer in than it is with the adapter, but I also don't really want to have to pull my nice clean, new engine apart again lol. The oil filter housing is pretty easy to swap, but for now I will see how things go with the adapter. Worst case, the response is slow or gets cooled by passing air and I swap on the machined housing.
(http://www.e30tuner.com/assist/e36x/e36x050.jpg)
Here it is with a bit more light. The connector is sort of trapezoid shaped and in this orientation it has about the maximum amount of clearance. here it is with more light.
(http://www.e30tuner.com/assist/e36x/e36x051.jpg)
I then unscrewed it a quarter turn to get the wide side of the connector & boot aligned with the knock sensor, and I still had ~1mm of clearance. So, even if when this thing gets installed for real it aligns in this "worst case" orientation I will have clearance (more than this actually, since it will be at least 1mm further toward the housing when fully tightened and compressing the crush washer properly). The knock sensor definitely needs to be pointing toward the rear though, as it would interfere if the wire was coming out toward the front. Anyway, I breathed a small sigh of relief once I saw that things would fit well. I could have always bought myself 2-3mm more by eliminating the boot since the connector uses individual wire seals which provide some protection & strain relief, but I am happy that the boot will fit (it is an "extra" from a 3-position JPT plug from a hacked-up harness).
(http://www.e30tuner.com/assist/e36x/e36x052.jpg)
That's it for now. I have other non-car stuff I want to focus on for the rest of the long weekend lol. On the one hand I enjoy projects like this, but on the other hand I can get carried away with them and put way too much mental energy into them. I can feel that I need to take a step back and occupy myself with some other stuff for a week or two!
-
I fooled around a little today to finish up the ICV installation plans. Since the 3D printed brackets seemed to get it where I wanted, I had some little 3/32" mild steel bits laser cut for the final bracket. I will be sending these out for black powdercoating this week as well.
(http://www.e30tuner.com/assist/e36x/e36x053.jpg)
I have a little mini-brake that fits in my vise, and it was the perfect little tool for the job. I once used it to bend a 2" wide piece of 1/8" steel, and that was definitely the upper limit of what this thing is intended for. These little things were no problem at all though. I bent them, took them out to compare to the 3D print by holding it against it, put it back, bent it a little more, checked, etc., until it came out just right. The first one had a little oops in that I started bending it from the wrong side, but I straightened it out and proceeded to bend it the other way. Still, I could tell that the metal was getting a little fatigued, so it's good that I had 2 of them cut.
(http://www.e30tuner.com/assist/e36x/e36x054.jpg)
Here is the final part. They were fully deburred and polished on my pedestal buffer using a convolute wheel ("Scotch Brite wheel"), but since they are just mild steel they will be getting some nice matte black powder coating. If anyone wants to use an M50 ICV, shoot me a PM and I'd be happy to sell you the second bracket at a very reasonable price lol.
(http://www.e30tuner.com/assist/e36x/e36x055.jpg)
Using it to mount the ICV, everything was exactly where I wanted it.
(http://www.e30tuner.com/assist/e36x/e36x056.jpg)
The next order of business was to get the hoses sorted out. Thankfully, there is an off-the-shelf solution that only required a little extra work. HPS makes some silicone reducing elbows which also have a fairly tight radius. The following parts were used (you can also search the PNs on Amazon and get them from resellers for less + free shipping):
https://hpsperformanceproducts.com/products/hps-16mm-22mm-black-silicone-90-degree-elbow-reducer-reinforced-hose-htser90062087blk
https://hpsperformanceproducts.com/products/hps-16mm-1-inch-black-silicone-90-degree-elbow-reducer-reinforced-hose-htser90062100blk
(http://www.e30tuner.com/assist/e36x/e36x060.jpg)
I had to go through a few rounds of test fitting and trimming, but it worked out well.
(http://www.e30tuner.com/assist/e36x/e36x057.jpg)
Here is how they fit after I finished with the trimming:
(http://www.e30tuner.com/assist/e36x/e36x058.jpg)
(http://www.e30tuner.com/assist/e36x/e36x059.jpg)
The only "questionable" part of this was the fact that I ended up shaving the barbs off of the dummy ICV. I was able to get the elbows on over the barbs but it was a giant pain and the fit was not amazing after trimming them and having the barbs up in the start of the 90 degree turn. If the hoses were for high pressure fuel I would not remove the barbs, but this is just the ICV which is never actually under positive pressure, so hose clamps will be just fine I think. I will do a much better job of shaving down the actual functional ICV that I will be using.
(http://www.e30tuner.com/assist/e36x/e36x061.jpg)
The other thing I took care of was making sure that my MAF removal plans were going to work. As you can see from my setup, all I really need is a straight tube section.
(http://www.e30tuner.com/assist/e36x/e36x062.jpg)
And wouldn't you know it, HPS sells the perfect part. No need for any fabrication at all, other than a little de-burring of the sharp edges on the ends. This is the part:
https://hpsperformanceproducts.com/products/hps-2-3-4-inch-aluminum-joiner-pipe-tube-tubing-bead-roll-4-inch-long
(http://www.e30tuner.com/assist/e36x/e36x063.jpg)
Here it is installed. It will also be powder coated in matte black with the ICV brackets.
(http://www.e30tuner.com/assist/e36x/e36x064.jpg)
That's it for now. The remaining mechanical items for me to do are to machine the fuel line tee for the PST-F1 sensor and to machine the intake manifold for the PST-1 MAP+IAT sensor. From there it is all wiring harness construction.
-
It's been a little while since I have been able to get much done on this project as work has been extra busy lately and home life also has its demands. But, here's a little bit of progress.
Here is the M50 ICV after I belt sanded the barbs off and then smoothed things out with a convolute wheel. The silicone hoses go on a lot more easily now.
(http://www.e30tuner.com/assist/e36x/e36x065.jpg)
I got the powder coated parts back, and they look really nice in crinkle black. It seems a little coarser and glossier than what I had done on the adapter plate for my M30 air box, but a little dust and dirt should make the tube blend right in, and nobody will ever see the ICV bracket anyway.
(http://www.e30tuner.com/assist/e36x/e36x066.jpg)
The bigger thing that I finished was the quad wheel speed sensor conditioner. This one was properly laid out and works really nicely on my bench test setup. Noise rejection is good while still being VERY sensitive. I designed a little clamshell enclosure to 3D print for it which would keep it safe and integrate some little rubber grommets.
(http://www.e30tuner.com/assist/e36x/e36x022.png)
(http://www.e30tuner.com/assist/e36x/e36x023.png)
(http://www.e30tuner.com/assist/e36x/e36x024.png)
I kept it fairly simple and easy to 3D print. Initially I thought about integrating some little flexible snaps to hold it together, but tapping screws are a lot easier in the long run, and won't get brittle over time. Also, I would have had to change the print orientation a lot to make strong snaps, which would have meant a bunch of support material being laid down inside the enclosure, and that just makes a mess so I avoid it whenever possible.
(http://www.e30tuner.com/assist/e36x/e36x025.png)
It all came out nicely and everything fit well.
(http://www.e30tuner.com/assist/e36x/e36x067.jpg)
(http://www.e30tuner.com/assist/e36x/e36x071.jpg)
I had a small batch of PCBs made for this. Folks who want one for their ECU projects can PM me and once I have a feel for how many people are interested, I can order more components and assemble them. The automotive qualified parts, particularly the MAX9926's at ~$8 each, are costly enough that I want to know exactly how many I need to order.
(http://www.e30tuner.com/assist/e36x/e36x072.jpg)
Here it is all assembled, cleaned and sitting in its new home.
(http://www.e30tuner.com/assist/e36x/e36x069.jpg)
(http://www.e30tuner.com/assist/e36x/e36x070.jpg)
(http://www.e30tuner.com/assist/e36x/e36x068.jpg)
-
How do you propose mapping this aftermarket ECU? I don't know of a way to determine the factory settings. The way I would proceed is to run a basic map that you can download from LINK for this engine and see how it runs. I would then get it on a chassis dyno to set the various tables. I haven't done this myself, but I'm thinking someone in the Austin area can do this.
I'm sorry if you discussed this already, but I just view your post and it gets rather involved. I'm impatient.
-
Sorry there have not been too many updates, I am taking a break from this project due to work and family obligations at the moment. The E30 runs pretty well on stock management as well, so I am going to enjoy it for a bit longer, and I am due to emissions testing later this year, so I am going to keep it in the current state since I know it passes lol.
Anyway, as far as mapping I am going to have a professional tune made for it, probably by Sssquid. He has done the factory remapping for me and can probably "translate" a lot of it into a decent base tune. After that, I may just drive the car out to Missourri for some live dyno tuning. My experience working with a "real" tuner has made it clear to me that those guys are going to do a better job on a tune than I am since they have thousands of hours of experience with it and I don't, and they will get the tune done faster than I would too. It's well worth the cost. I'm not going with the Link system because I want to DIY the tune...I want the modern control features and improved throttle response it provides.
-
Long time no update...
I am still not 100% back to working on this since I have told myself that I will finally deal with the full repaint this fall, but in the interim I have a little time to poke at the ECU project and do some basic legwork. As such, I finally planned out the wire arrangement for the main run that goes from the ECU to the firewall. It always irked me that the factory harness had some wires sort of twisted around one another, and there was a lot of "extra" wire here and there due to how mass production works with these things (harnesses are built out of sub-harnesses in most cases). Well, this sucker is a "too much time on my hands" special one-off, so none of that needed to be left in my new and improved one!
Now that I am 99% sure of the final ECU pinout, I was able to build a map for the ECU connector entry. Things will be getting a little tight in there, so there can't be any unnecessary crossing or layering of wires as they come in. The general idea is to separate wires by "type", and to have them stacked in a closest-to-farthest-terminal way which will be most space-efficient. I am not about to go crimping terminals on and putting them into the housing yet since I want to do that in the actual car, but it is also the case that I wanted to have the wire runs through the large sheath be approximately stacked in the proper order.
I built a little wire layout map based on the connection types and positions. All of the high and mid-current stuff is shielded, with the "S" wires being the shield taps that will be joined outside of the connector housing. Knock, crank and cam sensor wires are also shielded.
(http://www.e30tuner.com/assist/e36x/e36x075.png)
(http://www.e30tuner.com/assist/e36x/e36x076.png)
If anyone wants the vector art template for a mostly-properly-scaled 88 pin connector (Motronic side) and the mating connector entry opening, it is here:
http://www.e30tuner.com/assist/e36x/...e_Template.svg
So, I put together another basic pin board and got things labelled, sorted and arranged with an absolute minimum of twisting and crossing.
(http://www.e30tuner.com/assist/e36x/e36x073.jpg)
(http://www.e30tuner.com/assist/e36x/e36x074.jpg)
I am also going to re-design some of the sensor adapters and stuff. The previous ideas were nice and fancy looking, but too much hassle to actually make. I can get the job done much more simply. The main thing that I want to change is the oil pressure+temperature sensor position. I had been planning to install it in place of the stock oil pressure switch, which would be fine and could be done with a simple adapter, but the thermistor would be well out of the actual oil flow and probably read 10-20 degrees cool. At this point, I think that I will have a little mount boss TIG'ed onto the upper portion where the filter element is. Yeah, it is on the dirty side and if somehow the filter got clogged it would not indicate loss of pressure on the clean side (although the housing has an emergency bypass valve), but I don't plan to forget to change the oil or filter for 100,000 miles lol. An additional benefit of having the sensor up there is that I can use the Bosch Motorsport knock sensors since there will be room for the front one again without the oil sensor down in the way. The stock M42 ones are fine, but I would prefer to not deal with sensors that have integrated wires and which might go out of production at some point.
-
I have been back on this project a bit in the recent month. Most of the updates are on r3v, but for anyone on here who has been following this thread, here's an FYI that there's progress! Check the thread on r3v for the latest updates.
https://www.r3vlimited.com/board/forum/e30-technical-forums/engine-drivetrain/alternative-tuning-w-a-r-megasquirt-etc/9961647-m42-ecu-conversion-link-g4x-e36x