Dyno runs today

[SpencerM3]

Not sure if S50 injectors are compatible with M20 engines, but 95 M3's (maybe even 325's) have 17# injectors that can be found dirt cheap.

One step up from their are the 21.5# injectors in the 96-99 M3s.

I thought my '95 M3 had 21.5's in it, hmmm. I changed them out for 24# when I added the cams and hfm. Wish I had kept the old ones :(

Nope, they run the tiny 17# units, which barely support the stock motor.

Check ebay. I've seen them go for $20-50 on there for a full set.

[Digitalwave]

I am running lean to. I think I have a vacuum leak somewhere along the line. Never would have guessed since the car idles perfectly and such. What is the proceedure for finding a vacuum leak?

[KenC]

What is the proceedure for finding a vacuum leak?

When the engine is running, spray some carb cleaner on the vacuum and intake hoses. If your idle fluxuates, then you have a vacuum leak.

[C ///M]

cough...dinan chips are crap...cough. Seriously though, Dinan ecu chips are too conservative. I think you'd see/notice a difference with a different chip along with fixing the mixture.

[EVOIIIM3]

DO NOT THROW PARTS AT THE CAR!

There is a reason for it being SO lean! Find it first.
Make sure you are telling the ECU you are at WOT, check the TPS and throttle linkage.

Also, IMHO, junk the Dinan chip and get another one.

I would check the Fuel pressure regulator, and vacuum line. Also check for intake leaks. The nest thing is to test the fuel pressure.

IF everything is OK, try a adjustable rising rate FPR.

I bet you would pick up some power if you can get the AFR around 13.0-13.5 You should NEVER, read, NEVER be above 14.1 at WOT!

[SlammedE30]

That kinda sucks man. I hate it when the dyno is disappointing :? My car made 149/149 on a Dynojet and it was stock save for a JimC chip. Once again proving it's useless modding M20's. Best of luck with the fuel curve.
-Ted

[brodee]

There is a reason for it being SO lean! Find it first.!

I think that the reason is there is so much done to flow the engine better but nothing was ever done to increase fuel flow.

Believe me I will check everything before just "throwing parts at it", but I think you'd have to agree that larger injectors should have been part of the other mods done to the car in the first place.