Custom GSXR ITB for M10

[84driver]

This M20 ITB post got me thinking, so I started looking for more info.

Apparently the 2002 guys have done a couple M10 ITB on the cheap with GSXR ITB.

Example before installation (from here: http://www.bmw2002faq.com/component/...2f6923545550e/)


Example installed (from here: http://www.bmw2002faq.com/component/...3982/t,274960/)






Here's a bad DIY writeup with broken pics from e30tech :weak::

http://www.e30tech.com/forum/showthread.php?t=20141

I can't find any good examples of a currently running motor with these ITBs. I wonder if an s14 intake could be adapted so the AFM could still be used?
EDIT: Like this S14B20


Anyway, I'm unlikely to do this mod but it is food for thought.

[Jaxx_]

I don't know why you'd waste your time doing ITBs and keep an AFM/L-Jet. seems like backwards thinking to me.

[84driver]

Modular upgrade. Smoother power and better response. If budget wasn't an issue I'd just get a set of Alpina m10 ITB or S14 ITB + adapter and be done with it.

L-Jet can be tuned for larger injectors and a turbo if careful. The S14 runs fine on Motronic.

[Jaxx_]

Modular upgrade. Smoother power and better response. If budget wasn't an issue I'd just get a set of Alpina m10 ITB or S14 ITB + adapter and be done with it.

L-Jet can be tuned for larger injectors and a turbo if careful. The S14 runs fine on Motronic.

I just don't see this being cheap is the main thing. How is this modular? Is it totally plug and play? I didn't really read much of those threads.


I would not want to run L-Jet for a turbo with a decent spark map. At this point I don't think I would put that much time and energy into a turbo build and simply keep the stock EFI system because it "can do it." I want something that can do it well. tuning is where you make your power, not the amount of boost, as I'm sure you're aware. Can you even hookup something like SAFC? I mean that still leaves a dizzy issue even covering fuel(which is doable on a budget--FPR and bigger injectors).

Just spouting my ideas here.

[MikeDE]

If not having (2) kidneys wasn't an issue I'd just get a set of Alpina m10 ITB...... .

I just saw a set of these go for ridiculous monies.

[Hey_You]

Unless I was building a race engine (or a show car), I wouldn't bother with ITB's. Modern vehicles don't use them (most) and they run better (smoother/responsive). It's all in the engine management. If you want your vehicle to run smoother or more responsive, get a different management system. I'm with Jaxx on this one, it's not cost effective, and in the end, you are still limited by the L-Jet

[84driver]

lol

No one is in the M20 thread or on 2002faq telling those guys that ITB is a bad idea. I swear r3v thinks the M10 forum is just for coming to tell people which way is up

I just don't see this being cheap is the main thing. How is this modular? Is it totally plug and play? I didn't really read much of those threads.

I would not want to run L-Jet for a turbo with a decent spark map. At this point I don't think I would put that much time and energy into a turbo build and simply keep the stock EFI system because it "can do it." I want something that can do it well. tuning is where you make your power, not the amount of boost, as I'm sure you're aware. Can you even hookup something like SAFC? I mean that still leaves a dizzy issue even covering fuel(which is doable on a budget--FPR and bigger injectors).

Just spouting my ideas here.

SAFC is for MAP, an L-Jet runs on AFM, there is no direct or simple conversion. Furthermore, ITBs themselves need a custom vacuum manifold to run a MAP sensor, tuning an M10 with ITB and MAP sensor has been reported difficult (although Good&Tight managed it after much trial and error). Some have found success using a fully-variable throttle position sensor instead (aka Alpha-N).

Some more on that here:

http://77e21.info/megasquirt.htm

It is certainly possible to run a modest amount of boost tuned with L-Jet and the engine can be fun and last for years. I'm collecting these tips in my other thread:

http://www.r3vlimited.com/board/showthread.php?t=225906

I just saw a set of these go for ridiculous monies.

Right. Anyone can throw money at a project but most of r3v is about the learning experience and journey of DIY. Multiple vendors sell M10 ITB kits for $1000+ but that is definitely not cost-effective.

Unless I was building a race engine (or a show car), I wouldn't bother with ITB's. Modern vehicles don't use them (most) and they run better (smoother/responsive). It's all in the engine management. If you want your vehicle to run smoother or more responsive, get a different management system. I'm with Jaxx on this one, it's not cost effective, and in the end, you are still limited by the L-Jet

e30 320is and m3 S14 use ITB. e92 m3 uses ITB (and so do a long list of BMW engines). Nissan's rb26dett and sr20det combine turbo with ITB for great throttle response while retaining low-end torque.

Good & Tight ran ITB with his M10 turbo, here is the reasoning behind it:

http://www.e30tech.com/forum/showthread.php?t=32933#8

http://www.e30tech.com/forum/showthread.php?t=47286#7

The throttle response now is kinda slow with the large TB, so i've decided to go with the itb setup. This should help spool the turbo faster and make more power also, the stock manifold has to be robbing power.

Get a set of TB's from a 750 GSXR, different years have different size's. I made one for my turbo M10 w/42mm TB's and the throttle response was incredible.

Some more good info on ITB here:

http://autospeed.com/cms/A_3049/article.html

“If you’re prepared to wear some extra intake restriction, you could use an airflow meter feeding a plenum before the throttles - but that makes it harder to make big horsepower. I guess in a street car you really need to have the throttles connected to an air cleaner anyway so, generally, that means you’ll need some kind of plenum. So it could work in a street car.”

The vacuum assist from the manifold would be nice for brakes etc. I could build up the M10 running a turbo with say 8psi boost, ITB, still run L-Jet and I think it would be a blast to drive as a DD. Plus it would have a great sound.

Then after all that is together if I want to build it up for race power I can mess with doing a custom vacuum setup for a MAP and do an Alpha-N + MAP blend tune which is ideal for such a setup. In the meantime it'll make a mean DD and show car. I wasn't going to seriously consider ITB since I can't weld yet... but now after all this I want to do it just because racecar.

[Jaxx_]

No one is in the M20 thread or on 2002faq telling those guys that ITB is a bad idea. I swear r3v thinks the M10 forum is just for coming to tell people which way is up

If you run something that can flow it, it isn't a problem or a bad idea. Not to mention M20 MOTRONIC management is lightyears better than L-Jet. M10 motors can run strong, but not on stone-age technology. In the 1/4 my trap speeds increased 11% (just on a rough base tune) simply from running megasquirt. I also ran just under 1.5 seconds faster than stock.

SAFC is for MAP, an L-Jet runs on AFM, there is no direct or simple conversion. Furthermore, ITBs themselves need a custom vacuum manifold to run a MAP sensor, tuning an M10 with ITB and MAP sensor has been reported difficult (although Good&Tight managed it after much trial and error). Some have found success using a fully-variable throttle position sensor instead (aka Alpha-N).

SAFC is for any MAP/MAF signal that is going to an ECU. It modifies the signal going to it so it sees more/less depending on RPM and load. You could make it work if you cared enough to piggyback L-Jet(I'm telling you, waste of time).

And you can run a MAP sensor with multiple TBs, you pool them into a central box(vacuum canister), and run a restrictor if you need to. It isn't rocket science, but you probably will have a rough time convering L-Jet to a map sensor.

Some more on that here:

http://77e21.info/megasquirt.htm

It is certainly possible to run a modest amount of boost tuned with L-Jet and the engine can be fun and last for years. I'm collecting these tips in my other thread:

http://www.r3vlimited.com/board/showthread.php?t=225906

I think you have a lot to learn, sir.

1) the thread you linked to about increasing redline affects your entire fuel table.
2) in the thread about l-jet variables "big injectors are hard to find" is absolute BS. L-Jet can drive any high impedance injector. It's not like they're hard to find. If you want, they can go upwards of 1000CCs.
3) in post 2, setting base timing and having no advance is the most retarded shit i've ever heard, even for a cheap turbo setup.

Right. Anyone can throw money at a project but most of r3v is about the learning experience and journey of DIY. Multiple vendors sell M10 ITB kits for $1000+ but that is definitely not cost-effective.

wait, are you saying fabbing up a new DIY ITB setup just to run it through a restrictive AFM is cost-effective? I mean, you will learn...

Good & Tight ran ITB with his M10 turbo, here is the reasoning behind it:

http://www.e30tech.com/forum/showthread.php?t=32933#8

http://www.e30tech.com/forum/showthread.php?t=47286#7

I could build up the M10 running a turbo with say 8psi boost, ITB, still run L-Jet and I think it would be a blast to drive as a DD. Plus it would have a great sound.

and again, you run into the main issue -- how do you flow more into the AFM? once it reaches 100% load you can't add more fuel simply by adjusting a table. There's so much more you're not even considering and it's just baffling to think you'd run ITBs and a turbo on L-Jet.



You need to think about this for a second. L-Jet was designed in the 70s. It's fucking old. It doesn't have the resolution that modern ecus will have, nor the capabilities. There's a reason people don't waste their time. Believe me, I did all this research too, that's why I run megasquirt.

[84driver]

AFAIK there is no SAFC that works with our rising-voltage L-Jet AFM, but I'd be happy to see an example that shows otherwise. I know MAP + ITB is possible, hence mentioning Good&Tight's example. But I don't have time to write a book about what I know about engines so that you and I can internet-argue about how right we are.

Obviously there is no single source for perfect L-Jet and M10 tuning info. But somewhere in all the posted examples there are great ideas and mods that work well. If you have useful L-Jet tips to add, you're welcome to put them in my L-Jet thread. If you have interesting ITB facts you can add them here. If you just want to tell me what you think I should do with my car you're going to have to start a thread for that.

BACK TO ITBs

[Jaxx_]

People only want to hear the answers they want. I won't clutter up any more of your threads or waste my time with replies.

[84driver]

Here's an M10 with ITB with what appears to be an S14 airbox and 318i L-Jet:

http://www.youtube.com/watch?v=om_i4k1BF78&sns=em

[Hey_You]

e30 320is and m3 S14 use ITB. e92 m3 uses ITB (and so do a long list of BMW engines). Nissan's rb26dett and sr20det combine turbo with ITB for great throttle response while retaining low-end torque.

I'm not saying it can't be done, but you want to retain L-Jet, it makes no sense. The rb26dett and sr20det DO NOT USE ITB's stock. The e30 320is was also not an m10, and when they switched it from L-Jet to Motronic, gained power from a better management system. It too (m20b20) did not use ITB's. BMW uses ITB's with their M-engines. Do you ever wonder why they don't put them on EVERY engine they made? The 2002 guys that put ITB's on do it, but they don't use it with L-Jet, that would just be stupid. They upgrade to Megasquirt or some other Standalone. The m3 s14 uses them, but that engine has a RACE PEDIGREE