single throttle bodies S14

[hoevesruperd]

does single throttle bodies and injector+fuel rail from an M3 S14 fits on an M42?

[RED IS 91]

I believe that the spacing is wrong so it won't match up .............
This has been discussed before

[Boyracer]

Will not fit directly because cylinder spacing is completely different. Of course adapter can be made but it is bit difficult.

S50 throttle bodies from E36 M3 has identical cylinder spacing but even they require adapter too because cylinder head and throttle body bolt/hole patterns are different. Needed adapter is much more simpler than with S14 TB's however.

[bmwman91]

Look around for GSX-R throttle bodies.  They take some customization, but they are cheap and readily available.  A few folks have used those I believe.

[gearheadE30]

BTW it is the euro M3 that had individual throttles, not the American one. We basically got a warmed-over M50, and europe had about 321 hp to our 240.

[Froos]

BTW it is the euro M3 that had individual throttles, not the American one. We basically got a warmed-over M50, and europe had about 321 hp to our 240.

E36?

[gearheadE30]

Yeah, the e36. My bad.

The m50 based motors have the same cyliner spacing as the m42. The s14 is m10 based, so all of the dimensions are different.

[hoevesruperd]

thanks! i found S14 throttle bodies for cheap, so here's the plan, i'll buy a s14 gasket and a m42 gasket to have the right dimensions, i'll do an autocad drawing of the adapter and get it machined at school. sorry if this has been discussed about before. i'll find informations by myself and post pictures in the profile section for those interested.

[tony92ic]

I hate to throw cold water on the idea, but...

Before you try to build a system from scratch read this article and think about the issues you face.  

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

The first one would be "are S-14 throttle bodies too big?" They are designed for a car with nearly 30% more volume than ours. The M42 has a torque deficiency as it is. Can you afford to give some up with a throttle body set up that is too large? Actually the article implies nearly all individual throttle body set ups will give up bottom end torque while the gains are all at wide open throttle. Is that acceptable for your application? In a street driven car I would guess not normally. Unless maybe you are SheldonJace. (Sorry. I meant that as a little good natured ribbing.)

Second is "If you are doing this on the cheap are you willing to spend the money on the upgrades to make them worthwile? More aggressive cam, megasquirt system, a ton of dyno time tuning the system?

Dbilas says their system is good for about 20hp as a bolt on. Is all the time and effort worth 20hp (assuming you do as good a job as a bunch of engineers with years of experience building these systems)?

Sorry, I hate it when somebody throws a dose of reality into my projects, but usually I end up with a better thought out project in the end.  

Good Luck!  I am rooting for you either way.

[hoevesruperd]

I hate to throw cold water on the idea, but...

Before you try to build a system from scratch read this article and think about the issues you face.  

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

The first one would be "are S-14 throttle bodies too big?" They are designed for a car with nearly 30% more volume than ours. The M42 has a torque deficiency as it is. Can you afford to give some up with a throttle body set up that is too large? Actually the article implies nearly all individual throttle body set ups will give up bottom end torque while the gains are all at wide open throttle. Is that acceptable for your application? In a street driven car I would guess not normally. Unless maybe you are SheldonJace. (Sorry. I meant that as a little good natured ribbing.)

Second is "If you are doing this on the cheap are you willing to spend the money on the upgrades to make them worthwile? More aggressive cam, megasquirt system, a ton of dyno time tuning the system?

Dbilas says their system is good for about 20hp as a bolt on. Is all the time and effort worth 20hp (assuming you do as good a job as a bunch of engineers with years of experience building these systems)?

Sorry, I hate it when somebody throws a dose of reality into my projects, but usually I end up with a better thought out project in the end.  

Good Luck!  I am rooting for you either way.

thanks that's really helpful. i appreciate that kind of honesty. i have all winter to think about what i'm going to do with the car and save money. i don't need a race car either, its more of a challenge and project. i don't really need torque or horsepower since i ride the bus to school and work to save petrol for the fun months of the year. i'll be reading about it and collect ideas.
thanks again for your honesty