Difference between pre '88 m30's?? - BMW Forum

WALSRU · 11-13-2006, 07:18 AM

I have a bimmer again!

Well, I will as soon as I get it here from PA. It's a 1985 535i that I'm planning on tuning a little bit. What I was wondering is this: Why does the post 1988 m30 motor experience double the horsepower from a chip? Was there a difference in the motor or the ECU? Or is it simply going from a single pipe from front to back, over to duals? Anyone know?

WALSRU · 11-14-2006, 08:04 AM

No one? I might have to email turner or something.

Post 900 btw

. Man that took forever.

jbd5015 · 11-14-2006, 02:33 PM

There were 2 styles of M30 that went into the 5's. Anything that is 88 and up is the M30B35, which has a bigger intake, bigger displacement and higher compression, and with that comes i think a different, not necessarily better Motronic. The 87 and below have the M30B34, which is what i have too. This motor is smaller, but very comparable and the best benefit is that it has a lower compression ratio. lower compression = better for forced induction. These motors have no trouble hittin ~330 whp, ~350wtq on a stock motor with a turbo/intercooler package. is it a 5spd? what color and everything?

-Jeff

WALSRU · 11-14-2006, 04:15 PM

For now I was leaning toward the traditional exhaust, intake, cam, chip, flywheel, dif. Still deciding whether or not that will be enough.

It's blue (repainted) and oh yeah, has to be 5spd

jbd5015 · 11-14-2006, 05:20 PM

niiiice. nothing like a blue E28, they pull off that color very well. Ive seen one around me a few times lately, i finally ran into the guy. 87 535is, the good front end and wing with sport seats. the intake isnt really necessary on these cars IMO, the cam will help out some, but even with a rebuild of the engine, keeping it NA will limit you to no more than ~250 to ~300 hp. The best upgrade would definitely be a diff. I picked up a 3.73 LSD from an 87 535is for $120!!. Cant wait to put it in my 6er. Good looking car man. BTW, i have an M-Technic wing for a 5er and a 535is front air dam if interested...both would need to be painted to match but wouldnt cost much and make the car look mean!

-Jeff

WALSRU · 11-14-2006, 08:46 PM

250-300hp might be enough for now

I'm going to leave the bumpers as is for now, in case it's a real harsh winter. After that I'm going with the full BMP kit and euro lights.

jbd5015 · 11-14-2006, 09:04 PM

I see, so this beast is going in the snow? You def dont want the stock 535is front air dam then. Once they crack, there isnt much you can do, but if you can find a fiberglass front end, then at least you can repair it urself and then spray it! This should be a fun car, what are you looking to do with the suspension? you could always go for a set of the big brakes that will go really well with a minor suspension upgrade, making your speeds going into and through corners faster.

-Jeff