Quick ITB update

[tim_s]

Not been on here for a month or so, so thought i'd share a pic or two of the completed ITB setup:







still needs a bit of work, but is basically finished now. sounds as quiet as factory unless throttle is wide open, even then its still fairly quiet. im happy with that, as its my daily and i really wanted to keep the noise levels down. performance is good, but i need some more mapping work yet

[nickmpower]

i'd love some itb's but would hate having to do all the specail tuning for them, though i may need to so some of that anyways. What is the going rate for a set of the TB's over there? hows the power increase?

[D. Clay]

Looks good. How about a write up and info on parts sources, etc.
I love the air box. Very Nice.

[silverblades181]

I'm definatly interested in more details! Are you doing full engine management?

[tim_s]

thanks guys! i think a writeup would be a bit premature, I'm sure this setup will evolve quite a bit from here. there are still a few issues to sort out such as an unidentified air leak, only being able to open the throttle to (very!) nearly full throttle due to the linkage then knocking against the fuel rail, the airbox moving ever so slightly when the throttle opens (worrying me as far as reliability/longivity is concerned) for starters. these are only small niggles that will be resolved when i have some time.
im not sure about the performance gain as yet. i did the final fitment just before i went abroad for a month, at the time I thought it was fast but not hugely faster than with the standard throttle body. since I've come back however I've decided that it feels really quick, so its anyone's guess really. i have an MOT (yearly inspection) at the end of the month, it will hopefully be dyno'd while there - and compared to the figures on the same rollers earlier this year with the standard engine. of course i have the high compression 2.1 engine in there too, so its going to be very difficult to tell exactly what the gains are with the ITBs. I can say that once the few niggles are sorted, there should be no real drawbacks to running them, with my setup and trumpet length etc it seems to have as much torque throughout the rev range as before and seems to feel less strangled at higher RPM. I think to bring out the best of them I really need some new cams and the performance cyl head I'm working on. sadly i think it will be a while as I have other priorities.
I'm running megasquirt standalone for fuel and spark (the MAF in the pic is only being used as an extension tube - im using MAP), its only on a base map that is just about tolerable at the moment, I need to get an LC1 and do some mapping yet.
when completely finished I want 200bhp, impeccable daily driving manners and good fuel economy. a hell of a demand i know, but it should be attainable.

[StreetSpec_iS]

good stuff tim. I'l be in UK in October, would love to see this beast first hand depending on where you are.

[tim_s]

good stuff tim. I'l be in UK in October, would love to see this beast first hand depending on where you are.

no worries, pm me nearer the time. I'll be in london, but try to make it to most of the bmw shows too.

[silverblades181]

a video would be uber nice and is your goal 200 bhp or 200 whp? 200bhp doesn't seem that much with a 2.1 stroker and full engine managment...how much of a high revver will it be when it's done? (with the head and all)

[tim_s]

a video would be uber nice and is your goal 200 bhp or 200 whp? 200bhp doesn't seem that much with a 2.1 stroker and full engine managment...how much of a high revver will it be when it's done? (with the head and all)

Ok, I'll work on a vid! My goal is around 200bhp at the fly, its a realistic but conservative figure I reckon as I'm not going to go balls out just to get a slightly higher figure. The cams will be fairly tame regrinds for now, and i'll be revving the engine to somewhere around 7,2k-7,3k rpm. The power output really isn't a concern right now, I'm trying to get the setup totally reliable, looking factory and mapped to a very high standard to be smooth and have good economy etc, before working on getting maximum power output. also a strong power curve throughout the rpms would satisfy me more than high peak power.

[sheepdog]

Looks really good!
Engine bay looks very clean as well. You may want to look into Bmwman91's coil on plug system for that as it would make a nice addition.

[FL318is]

I like the whole concept.  Very nice engineering.  Tell us when we can expect the kit to be available.

[tim_s]

m totally with you sheepdog, i want to make the most of all the advantages that this engine has over the S14, and COPs would certainly be a really nice addition to the engine. It will have to wait for the moment though, as I'm being really strict with myself and making sure that any money and time I spend on her at the moment is towards getting her as close to factory smoothness and reliability as possible. Since previous posts on here I've rectified the plenum moving with throttle problem (the accelerator pedal stop just needed a bit of adjusting), fixed the air leak with some new O-rings on the throttle bodies, and have continued to work away at the mapping. I feel I'm getting closer to reaching the point where the setup can be described as complete, I just need to have the welding to the fuel rail done.
I'm quite desperate to get the new cylinder head finished and sort out some cams, but again I don't really have the time or money right now. Next month is the ultimate BMW show at santa pod, and I'll probably have to make do with the spec I have at the moment. I will do a 1/4 mile and dyno if possible there, I also have some dyno time locally penciled in. Of course, present figures with a standard head and cams will not tell the whole story though.


As for a kit, I haven't really any intentions to do one, but if there's interest, I'll certainly consider it! On a serious note, I certainly wouldn't mind selling my plenum (airbox) to someone, as I have plans for a CF one that is ever so slightly smaller. I have a guy lined up to build the CF plenum, only I don't have the 2 weeks to be without my current plenum that this would require. If there was interest in people having some of these built up from my specs, I could certainly ask the guy.
The main reason I haven't considered a kit is that I'm not sure how many guys out there are prepared to spend more than $1k in one hit on their cars. I've certainly put enough time and research into this setup that it could now be done as a bolt-on kit, and supplied correctly could be DIY fitted in a day easily, needing only a final dyno session to tweak the basemap to your particular car. there are some interesting benefits to be obtained with going MS and running these on a standard car, for example motorway and town mpg should improve, not to mention the improved throttle response (restrictionless intake) etc.

[FL318is]

It is certainly worth thinking about.  As for my car, when I get the basic mx items done I will be looking to make performance improvements.  I wil keep you posted.

[mohaughn]

Hey Tim.  How is this project going for you?  I'd be interested in what advice you could share on easily hooking up a MS.  It really doesn't seem like hooking it up would be that difficult if you know the proper points to tap into to, and you can tap into the connectors properly.  Probably easier said than done.

The difficult part comes when you have to tune it and get it running.  How transferable are your base maps?

I was pricing some things out yesterday and it looks like you can get all of the MS kit and LM1 for a little over 700$ assembled.  What else above that are the extra costs  for just getting the standalone up and running with MAP?  Any benefit to run MAP and MAF if not using ITBs?  Thanks.

[tim_s]

Hooking up megasquirt isn't too tricky as you've suggested. I managed to keep most of the original loom pretty much intact, you can't tell once MS is installed etc. I could also switch between motronic and MS by just swapping a molex connector over. Extra wiring mine has at the mo includes the IAT, the MAF wiring, and wiring for the fast idle valve I use to control idle.
Tuning is a very steep learning curve, its much more involved than with a piggyback etc. I'm not sure how transferrable my maps are, they're also not brilliant yet either. I have a bit of a love/hate relationship with megasquirt, i've been running it for a few months and still don't have maps that i'm happy with. The car does run ok and give good performance and economy, its just not anywhere near as smooth as factory atm. Its really depressing to have a car that i've invested quite a bit of time and money on, which used to run great on motronic with the 2.1, but with ITBs and MS runs fairly poorly. def take heed of this before undertaking to run MS, and make sure you have a fall-back plan (someone who can map it for you!).

On the standard engine MAP seemed to work pretty well, though I think I probably prefer MAF on balance.
Extra costs include things like adding coil driving circuits, darlingtons to power ICV or whatever, MAFs, injectors, filters, idle devices etc. Nothing too costly after the main outlay on MS and WBO2.
Its safe to say MS is a very big undertaking, I will get mine mapped properly by a chap I know when I have the time. I'm looking into running the car on LPG at the mo, over here its under half the price of petrol, as well as having a higher octane and much less emissions. I may use MS for this.