Author Topic: M42/M44 ITB Kit Design (Read 299202 times)

lambertius · « **on:** August 20, 2014, 06:51:19 PM »

Note: I don't make the kit, I helped design and test it. This thread contains all the info on the development. If you want to buy the kit, you can get it here! https://devil.design/product/bmw-m42-complete-itb-kit-for-e30/

Just a quick update!

I also thought I would post all the videos I've made for my car on the front page!

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Okay, I've had a chat with Rama regarding pricing of the kit. With the assumption that the current number of people who want to get in with the bulk order commit to the purchase , the prices will be (in USD, and they are subject to change):

Carbon Fiber Kit - $1500
Fiberglass Kit - $1400
Flywheel - $195 (He will do this price for JUST the flywheel as well if there is enough interest)

If you have an E30, as part of the bulk order Rama will modify the airbox for clearance if you want. All E30 kits will be supplied with the Carbon Fiber curved trumpet for cylinder 4 clearance.

Group buy ends on the 31st of May 2016 so message me if you haven't already!

Make sure you let me know what you want, what model your car is, the driving side and where you are!

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The final episode is up! I hope you enjoy it, I start talking about the kit about half way through. We tried to be as gratuitous as possible with the induction and exhaust sounds!

https://www.youtube.com/watch?v=k8Ay1x_H-9k

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I'm currently organising a group buy Please PM me if you're interested. Price will depend on the number of serious purchases. Let me know you car and driving side, whether you want the CF of FG airbox, what country you're in and if you want a flywheel as well. Cut-off date is the 31st of May 2016

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The kit DOES fit the E30 cars, but it requires some slight modification from standard so you will need to notify RHD that you want the kit for an E30 at purchase. The details are here at this post.

http://www.m42club.com/forum/index.php?topic=18442.msg130923#msg130923

So with nothing but good news for fitment, Rama has said that he is happy to take on a group purchase. Let me know if you're interested!

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The kit will fit LHD E36 cars and should fit the LHD E30 cars

***I've had to update this as I mistakenly stated that it had been fitted to an LHD E30***

This is one of the items that has come up in the survey, so I've gotten a bunch of photos of it fitted in a LHD car (E36, but it will should fit an E30). I've decided to post this on the front page as an update so that people will see it without having to go through the whole thread since it is a key thing people have raised.

We need someone to test fit the LHD E30 please PM me if you're interested. You will get some pricing perks, but will need to be willing to take photos to put up in the forum, and have some patience in case there are any clearance issues and the airbox needs to be modified. In all likelihood it should be a straight fitment.

If you haven't filled out the survey, please do - I know for sure that Rama will make a few adjustments based on the current feedback, so the more the better!

http://goo.gl/forms/qx17FaMQ7E

The kits getting packaged to ship

The kit comes apart in a modular fashion to suit your purpose I don't recommend smoking in your engine bay...

Production model LHD fitment

UPDATE

If you've been following this thread, or even if you haven't - could you please help me help out Rama - since it was him who made all this possible - and follow this link?

http://goo.gl/forms/qx17FaMQ7E

It will help him decide on what projects to follow up on in the future - like CAM & Stroker kits for example (you can even talk about different engines). There are only a few questions and I would really appreciate it!

EDIT: I can tell from some of the responses some of you would like me to know who you are - so if you would like me to be able to respond to you directly, please include your email!!!

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I HOPE YOU ENJOY THIS TEASER

https://www.youtube.com/watch?v=Y4kZcENnW_c

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THE KIT IS FINALLY READY TO PURCHASE

After more than a year in development, the kit is finally available to purchase!

http://racehead.com.au/products-page/bmw/bmw-m44-m42-complete-itb-kit/
http://racehead.com.au/products-page/bmw/bmw-m44m42-complete-itb-kit-carbon-fiber-airbox/
http://racehead.com.au/wp-content/uploads/2015/11/BMW-M42-44-itb-kit-instructions.pdf
http://www.m42club.com/forum/index.php?topic=18442.msg129970#msg129970

At the time of this post 01/12/2015 There are currently kits in stock, so if you want to get one without having to wait now would be the time! Prices are in USD.

I'm still continuing the RnD to test a few variations for my own personal satisfaction, but you're ready to rock with this as it is and it offers substantial headroom for other modifications! So you don't have to spend ages looking, here is the dyno results of just the ITB kit below:

There will be a couple more important updates to this first post, this is just the beginning!

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So I've wanted to put a set of ITBs on my car for a while as a fun project, and have been reading up on the options for a while. As far as I could tell there are 4 possible options:

1. The most common is to buy M3 ITBs, make an adapter plate for the port face and hook it all up. The pros to this is that the parts are easily available, and it has a vacuum bypass for the ICV and different vacuum lines already built which makes adaptation a bit easier. However you will still need to fabricate/alter an airbox as well as points for some of the vacuum lines.
2. There is an off-the-shelf kit made by dbilas dynamics which will fit with no effort, and accounts for all the peripherals and air lines no worries. It does cost more than common sense allows, considering the M42/4 engines aren't exactly power houses, so the incentive to spend heaps for not a whole lot of power isn't high. There is also a kit by extrudabody and GT Technic but they don't appear to be as complete.
3. Purchasing another brand of ITBs like Jenvey, and making an adapter plate for the kit. However, this is a bit more of an unknown and could require a fair bit of screwing around to make the kits fit.
4. Fully fabricate a custom kit which requires time and effort - and skills with metalwork...

There is one other big point which I haven't raised yet, and that is the dimensions of the ITBs that are used. I'm not an automotive engineer, and I haven't worked directly with engine design. I have done some analysis of fluid dynamics for different purposes, and through reading I have a fair general understanding of engine design. While trying to see what people had done with ITBs for this engine previously, I found that a lot of people had attempted it, but the threads I found never posted the results from the conversions. Considering the effort required to do this, I wanted to be sure that what I was doing was going to pay off. I had a suspicion that the M3 ITBs and the dbilas dynamics ITB kit were too large in diameter and would most likely result in a loss in power across the rev range rather than a gain. I also suspected that the runner length for both options was too short to suit the engine dynamics. Not being familiar enough with what was happening I decided to contact a race engineer and ask some questions.

After getting some answers and getting a bit more of an idea what I was looking for, I decided to run some very basic CFD analysis on different ITB diameter arrangements. Even with the basic set up that I used, it was immediately obvious that ITBs larger than 45mm would significantly under perform on the M42/4 engines. The pictures below show some low velocity analysis through the a number of different profiles - the further back the higher velocity profile sits within the ITB the better the cylinder filling characteristics will be (provided you don't choke/restrict the airflow) due to the higher air velocity carrying more momentum as well as having better resonance characteristics. The poorest performing ITB is a simplified model of the S50 ITBs on the M42 ports.

After a bit more back and forth with the engineer, he decided that he wants to make a properly engineered bolt-on kit for the M42/4 engines that will accommodate all the vacuum lines, have the correct dimensions, dyno charts to prove its efficacy and be affordable. He is okay with me sharing some of the progress as it happens, and I'll be contributing my car to the cause for testing. At the moment, we're designing parts to test fit and make sure all the dimensions are correct, as well as preparing flow simulations for real velocities and to model fuel mixing from different manifold shapes. Right now I'm preparing a few different manifold shapes for CFD analysis to best improve fuel mixing, below is a shot of the model for the manifold casting. This casting will be the basis for whatever the final version will be, but for the moment it will be analysed and altered according to the findings we make. I still need to model up the trumpets and the airbox, but I'm hoping to do a full transient analysis on the system provided I can find all the information I need. From the engineer's previous experience and my findings we're going for 42mm ITBs as they should line up well for the engine's parameters.

If people are interested in this project I'll update it with results as we get them and show why the decisions were made for different selections. And for anyone who is interested, I could probably use a hand obtaining any information as there are a few key things I've been searching for answers to.

These are the dimensions of the M42/4 port face that we measured, however if anyone could be so obliging as to measure their own engine port profile to let us know if they get the same values it would be a great help. Dimensions are in mm. Edit: We're pretty confident these values are correct now.

This is a simple sketch of the lower half of the intake manifold and its arrangement in the engine bay. The M42/4 is tilted at 30 degrees from vertical, however the port face is slightly recessed into the head. I believe the recess is at an angle of 5 degrees (35 degrees from vertical), however my engine is still in the car making it a bit awkward for me to measure so if anyone has an engine out and can confirm the measurement that would be great. I also measured the angle the injectors run into the manifold at 25 degree from vertical which was a bit easier because I had a spare manifold out of the car. Edit: We've revised the port face angle to be 40 degrees from vertical.

Anyway, that is the story so far and I hope people find this interesting! One of the cool things about this, is that this is all being done via telecommunication - I've never met the race engineer I'm dealing with in person as he is currently in a different country. I find that quite interesting that something like this can be done with such a significant physical separation. At some point I'll be getting sent test parts to fit and run and hopefully some good results!

Darky · « **Reply #1 on:** August 21, 2014, 01:39:12 AM »

Hi
Great idea building a dedicated kit for a m42, I will be watching closely.
The s50 itbs will fail because of cylinder capacity, but when you get your cylinder volume up they work quite well.
Cheers

lambertius · « **Reply #2 on:** August 21, 2014, 01:53:28 AM »

Quote from: Darky on August 21, 2014, 01:39:12 AM

Hi
Great idea building a dedicated kit for a m42, I will be watching closely.
The s50 itbs will fail because of cylinder capacity, but when you get your cylinder volume up they work quite well.
Cheers

Oh yeah, I could've probably been a bit more implicit in what I wrote - but you are correct, the M3 ITBs will work when *conditions* are met for them to work, but as a bolt on modification they are most likely detrimental. From what the engineer I was talking to was saying, there engine would need to be stroked and have the rev limit raised as well as having the ITBs on a thick adapter plate for them to work most effectively. What we're aiming for is a kit that suits people like me, who want to tinker on their own car but not necessarily putting in heaps of work. The idea being that you can swap this manifold in, adjust the slotted cam gears, exhaust and a tune and be done with it. Getting the most out of your engine without having to do an engine build!

I'm getting a simplified model ready at the moment for instantaneous flow analysis to make sure the flow characteristics are ideal, but in the meantime I do have a render of a draft/concept of the manifold. I always like the way renders look even when its a draft, so pro!

wazzu70 · « **Reply #3 on:** August 21, 2014, 07:54:36 AM »

Please keep this updated. 42mm sounds spot on. Most kits are too big like you say.

thebrelon · « **Reply #4 on:** August 21, 2014, 03:54:08 PM »

That's interresting! And I like the way you do it.
I've never been too interrested by ITBs as they often lack engineering/design but if you come out with a solution matched to our engines that could be tempting...

May I ask you what do you intend to do for engine managment? Because most ITBs setup are poorly designed and the rest poorly managed....
Do you plan to go stand alone (MAP/MAF/ALPHA-N?), keep the stock management and provide a chip?

MLM · « **Reply #5 on:** August 21, 2014, 05:30:31 PM »

Sounds interesting Lambertius. Unfortunaltly I cannot see your Pictures (may be me) But am looking forward to seeing you CFD results. Extremly good results can come from a optimised system.

lambertius · « **Reply #6 on:** August 21, 2014, 08:38:03 PM »

Quote from: MLM on August 21, 2014, 05:30:31 PM

Sounds interesting Lambertius. Unfortunaltly I cannot see your Pictures (may be me) But am looking forward to seeing you CFD results. Extremly good results can come from a optimised system.

I had some issues uploading them imgur yesterday, any better now?

Darky · « **Reply #7 on:** August 21, 2014, 09:39:31 PM »

Hi
Pictures are working now, and are awesome too.
Cheers

MLM · « **Reply #8 on:** August 22, 2014, 03:58:08 AM »

Yup pictures are now working. (I miss SW render package haha)

It looks like you have focused on various approaches to adapting a round TB of various sizes to port shape? The analysis appear show the criticality of transition change from one shape to another.

Have you considered taper over the length of runner? Viscous losses along the wall appear to be creating an increasing boundary layer tapering your velocity zone toward the port.

lambertius · « **Reply #9 on:** August 22, 2014, 08:56:31 AM »

Quote from: MLM on August 22, 2014, 03:58:08 AM

Yup pictures are now working. (I miss SW render package haha)

It looks like you have focused on various approaches to adapting a round TB of various sizes to port shape? The analysis appear show the criticality of transition change from one shape to another.

Have you considered taper over the length of runner? Viscous losses along the wall appear to be creating an increasing boundary layer tapering your velocity zone toward the port.

You're correct in your observations about what that initial simulation was, as well as the transitions and tapers affecting the flow characteristics. I'm actually in the process of running a new bunch of more 'realistic' simulations now with the primary purpose being to determine the most effective geometry of the taper and internal geometry so that there is the highest possible velocity profile. By changing the internal shape of the runner I've been able to add a few % higher velocity to the intake without reducing the cross-section or changing the length. Pictures will go up once it is ready to show!

lambertius · « **Reply #10 on:** August 23, 2014, 05:48:46 AM »

Quote from: thebrelon on August 21, 2014, 03:54:08 PM

That's interresting! And I like the way you do it.
I've never been too interrested by ITBs as they often lack engineering/design but if you come out with a solution matched to our engines that could be tempting...

May I ask you what do you intend to do for engine managment? Because most ITBs setup are poorly designed and the rest poorly managed....
Do you plan to go stand alone (MAP/MAF/ALPHA-N?), keep the stock management and provide a chip?

There really shouldn't be a reason to move away from the standard DME in either the E30 or E36 cars. The computer is versatile enough and is easily tuned by any reputable company. Dyno results will be part of this when it is done, so we'll be able to see for sure if the OEM computer is up to the task.

thebrelon · « **Reply #11 on:** August 23, 2014, 08:09:17 AM »

Quote from: lambertius on August 23, 2014, 05:48:46 AM

Quote from: thebrelon on August 21, 2014, 03:54:08 PM
That's interresting! And I like the way you do it.
I've never been too interrested by ITBs as they often lack engineering/design but if you come out with a solution matched to our engines that could be tempting...

May I ask you what do you intend to do for engine managment? Because most ITBs setup are poorly designed and the rest poorly managed....
Do you plan to go stand alone (MAP/MAF/ALPHA-N?), keep the stock management and provide a chip?

There really shouldn't be a reason to move away from the standard DME in either the E30 or E36 cars. The computer is versatile enough and is easily tuned by any reputable company. Dyno results will be part of this when it is done, so we'll be able to see for sure if the OEM computer is up to the task.

so you plan to keep the AFM on M42 and MAF on M44 and provide chips for both?
it will be interresting to see the results!

wazzu70 · « **Reply #12 on:** August 23, 2014, 05:56:38 PM »

An interesting point was mentioned about transitioning from the round throttle shape to the oval inlet shape. Most of the throttles are based off the old Weber side draft carb setup....but you would think by now oval throttles would be more available since most engines made in the last 20 years have this port shape.

lambertius · « **Reply #13 on:** August 28, 2014, 01:02:07 AM »

Quote from: lambertius on August 23, 2014, 05:48:46 AM

Quote from: thebrelon on August 21, 2014, 03:54:08 PM
That's interresting! And I like the way you do it.
I've never been too interrested by ITBs as they often lack engineering/design but if you come out with a solution matched to our engines that could be tempting...

May I ask you what do you intend to do for engine managment? Because most ITBs setup are poorly designed and the rest poorly managed....
Do you plan to go stand alone (MAP/MAF/ALPHA-N?), keep the stock management and provide a chip?

There really shouldn't be a reason to move away from the standard DME in either the E30 or E36 cars. The computer is versatile enough and is easily tuned by any reputable company. Dyno results will be part of this when it is done, so we'll be able to see for sure if the OEM computer is up to the task.

I don't think the guy who will be selling it will include a chip - I think that you will need to get it tuned in order to get optimal results, but by providing dyno charts he will be able to demonstrate the efficacy of the design and the gain by tuning the car for it. The E30/6 cars are easily flashed with a new tune so it will be something you will be able to get done anywhere there is a reputable tuner. This would be easier than a chip anyway since you won't need to install anything.

Quote from: wazzu70 on August 23, 2014, 05:56:38 PM

An interesting point was mentioned about transitioning from the round throttle shape to the oval inlet shape. Most of the throttles are based off the old Weber side draft carb setup....but you would think by now oval throttles would be more available since most engines made in the last 20 years have this port shape.

It is interesting that you mention that. If you have a look at the below image, the second flowsim from the top has a circular profile that has the same CSA as the oval profile, but in the isosurface image, the higher 4m/s air velocity doesn't extend back into the circular profile. I'm not 100% sure how to describe the effect, but the reason the ports are oval is that it increases the velocity with a minimal impact on drag - it basically improves cylinder filling. I'm not sure what the effect of having the butterfly being an oval shape would be though; I imagine that there would be a point where having the thinner profile too long would reduce flow by more than the increase in velocity (and therefore momentum) is worth. That is something for a Formula 1 team to investigate I suspect...

lambertius · « **Reply #14 on:** August 29, 2014, 03:50:12 AM »

So I've been running simulations since before I started this thread, but I now have enough to make an interesting enough post that will actually demonstrate in an empirical way the kind of benefits you could potentially see.

The simulation I ran was of a slightly different shape to the sand-cast manifold that will be needed to mount the kit. There are no injectors in the model as that wasn't what I was analysing at this point. There are two simulations I ran; one to assess a sharper curve in the manifold (which would give more hood clearance) and one that is steeper but gives less clearance. The results of interest are peak velocities around the valve, the mass flow through the valves, and visual observations of flow separation and turbulence within the casting.

This first images displays the boundary conditions, environmental pressure at the trumpet and a static pressure at the valve openings. These values at the valves were taken from experimental values and represent the kind of peak instantaneous pressures you would see when a cylinder is at the bottom of it's stroke.

Let's have a look at the steeper manifold:

The interesting things to note is that there actually quite a high peak velocity, and there is a good even flow through the manifold. However, you will notice that just after the transition into the ports there is a flow separation that takes place as the air is diverted into on of the two valves. This phenomenon doesn't occur in a shallower manifold:

You can actually see the turbulence clearer with this cut plot through the valves:

Steeper manifold:

Shallower manifold:

So the question is; how much does this affect the Air Mass Flow Rate?

Well the shallow manifold allows a flow rate through the valves of 0.1667 kg/s while the steeper manifold allows only 0.1649kg/s. Empirically the difference is only 1%, which is negligible - unless you're trying to optimise a system, which is kind of the point of doing this. However, the reason I'm showing you this isn't because of the difference it makes between two designs that we have, it is the difference between these designs and the stock manifold. Anyone who has seen the OEM manifold knows it is an Octopus, long, and with sharp curves - significantly more so than what is modelled here. The point of showing these results is that short of modelling the OEM manifold from scratch, this should illustrate that on the lower half of the manifold alone, there is the potential for ~5% better air flow since this is so much more direct than the OEM parts. The largest arc these models moved through was 35 degrees, the largest the manifold moves through is closer to ~120 degrees.

For me the real interest is the spot of stagnant air before the flow separates into the valves. It is indicates to me that it will be worth fidgeting with hood clearances to make the flow more direct so that fuel doesn't get stalled in dead air in front of the valves!

Another interesting thing you can see in these images the shock-wave that forms from the actual throttle butterfly. I'm currently playing with the design of the butterfly at the moment, but believe it or not - using the same diameter butterfly, but changing the way it interacts with the flow stream has so far yielded a 5% improvement in mass flow rate. I'm playing with alterations to that at the moment, but it will be the most interesting butterfly valve around!

Author Topic: M42/M44 ITB Kit Design (Read 299202 times)

lambertius

M42/M44 ITB Kit Design

Darky

Re: M42/M44 ITB Kit Design

lambertius

Re: M42/M44 ITB Kit Design

wazzu70

Re: M42/M44 ITB Kit Design

thebrelon

Re: M42/M44 ITB Kit Design

MLM

Re: M42/M44 ITB Kit Design

lambertius

Re: M42/M44 ITB Kit Design

Darky

Re: M42/M44 ITB Kit Design

MLM

Re: M42/M44 ITB Kit Design

lambertius

Re: M42/M44 ITB Kit Design

lambertius

Re: M42/M44 ITB Kit Design

thebrelon

Re: M42/M44 ITB Kit Design

wazzu70

Re: M42/M44 ITB Kit Design

lambertius

Re: M42/M44 ITB Kit Design

lambertius

Re: M42/M44 ITB Kit Design