2.7i bad acceleration

[e30onBBSs]

I wrapped up most of the engine and made it run at op temp, and it could still have problems, but it seems like it has less tug than the all eta it was before? It definitely revs higher but is dissapointing and I wasn't expecting much. It seems slower in first and second than third which is very strange. And I swapped in a 4.10lsd

Eta bottom end
I head everything up
Normal eta pistons
Injectors all spray evenly

- the only thing I'm "missing" is this 13711705064 it's the AFM plate. Could this really affect performance? It's "pre-afm" if you will but may be leaking in air?

As a side note, my car hard starts hard and is in need of a check valve but I'm probably going to just do fuel pumps. It loses pressure within hours. Could bad fuel pumps make it slow as hell? It idles and seems to run well when it's on.

Another thing- I can give it redline in when my driveway while it's not in motion, and it revs like an m20 should. While driving, I was in second gear and gave it WOT for probably 8+ seconds and it hits this kinda gummy spot where it just doesn't accelerate at all, but it also doesn't even hit redline back and forth like it can in the driveway.

[jeffnhiscars]

Did you do a motronic and injector upgrade

[e30onBBSs]

Dissapointed by 2.7i?

Did you do a motronic and injector upgrade

Yea it's all from a 1989 325is above the bottom end. Harness and all of course. I read about how the 325i injectors lean out but it's surpsisingly slow before the higher rpm's as well haha

[e30onBBSs]

Anyone have any ideas? I will take a video some time

[CondorH]

Eta Pistons with an I head leads to low compression ratio. Could that be it?

[e30onBBSs]

Eta Pistons with an I head leads to low compression ratio. Could that be it?

no sir. I'm thinking it may be the dif I swapped in now. It makes this weird sound until about 2k rpm then goes away, but it revs so well when its in neutral. IIRC before it ran at op temp it was faster.. we will see.

[JeLani]

Yea it's all from a 1989 325is above the bottom end. Harness and all of course. I read about how the 325i injectors lean out but it's surpsisingly slow before the higher rpm's as well haha

my car idled and warmed up horribly before i got 325i(14.5) injectors. after that it drove and ran amazingly. you could also run the m50(17.4#) injectors but those are ran in those motors at a higher BAR you it would be actually running less pressure (+15/16), unless of course you have an adjustable FPR

[supkev]

no sir. I'm thinking it may be the dif I swapped in now. It makes this weird sound until about 2k rpm then goes away, but it revs so well when its in neutral. IIRC before it ran at op temp it was faster.. we will see.

I have almost the same as you with 3.73 but with SETA pistons &etc. Mine boogies out the hole thats about it. Once I get to 4th or 5th it gets boring just falls flat.