2.5, 2.7 or 2.8 help?

[million]

Hi everyone I'm new here and new to bmw's and have just bought an early 1985 2.5 sport with what I'm told has a 5 series 2.7 engine in it; the economy lump (127bhp I think). The guy said if I were to use a 2.5i head coupled with an alpine 2.7 copy chip it would bring it right up to spec; is this right?

Anyway I'm keen to make a bit of a track day racer style beast and had ideas of 2.8's or 2.7's so I consulted fritz bits yesterday who pointed me away from the larger capacities and into the direction of the 2.5 due to it's rev range dynamics. My question is what do you guys think, what have you used/made and what do I want for a go faster track car?

Cheers

Max

[daveo]

There is a thread at the top of Engine Swaps / Forced Induction section which will all the info you need.

[ed325i]

The guy said if I were to use a 2.5i head coupled with an alpine 2.7 copy chip it would bring it right up to spec; is this right?

With 2.5 pistons and a change of cam.
You can get 200/220 bhp from a 2.7 but it not going to be cheap.

[million]

Yeah cool I read those posts about building the 2.7 and the other chaps posts about 2.8 builds which I already know about but it doesn't seem to answer my question about how they drive and what's best for tracks etc.

Thanks ed325i that's what I though as just by using the 2.5 head I would not get the desired compression. Good thing the car comes with the origional 2.5 then.

Regards

[ed325i]

what's best for tracks etc

318iS

[fowler]

supercharge it !!!! prob find that will be a track weapon