Tell me about m30 swaps

[madjurgen]

^^^
So what are you going to do?

[klrskies]

As we have seen the M20 block expanded up to 3.2 liters of displacement, thats getting pretty close to 3.5 of the M30, and it explains why BMW dropped the M30. It's technology was replaced with a more compact, lighter, and capable design that followed the evolutionary trend of the period. I agree that a torquey, tuned M30 (>= 260 HP) would be a nice engine in a street car. I have an M30 that I may use to do it. I would certainly move it back as much as possible to balance the car. They are inexpensive and rugged.

Currently I'm building a N/A 2.8 liter M20 using, "i" pistons, 130 mm eta rods, "i" head, and an M50, 84mm stroke, 2.8 crank. As a track/play car, I will probably end up tuneing it to around 210~220 Hp. The car is about 200 lbs lighter than stock with lowered / coil-over suspension. I know how extra weight feels on a performance car, especially on the front end. If I ever do the M30 swap, I would certainly move the drivetrain back as far as possible, perhaps even trying to modify the oil pump pick-up and oil pan to go even a little further back than position 3 to get better balance. I probably wouldn't turbo as it's getting pretty tight in the engine bay and the M30 would be a nice torquey street car anyway.

Yes, I agree, that on a street car, the weight would be much less of an issue and the torque would be alot of fun. But I think a turboed M20 would provide all power the e-30 chassis can utilize, be as economical to build and fit in, and minimize weight gain issue.

But I think the important thing is that the e-30 is a versatile chassis that supports several intresting drivetrain configurations. All of them are good! Enjoy it.

[Bimmerfanatik]

But I think a turboed M20 would provide all power the e-30 chassis can utilize, be as economical to build and fit in, and minimize weight gain issue.

The problem with turbo'ing an M20 is that it's a lot harder to tune than an m30 would be, there's a lot of variables and aftermarket parts to buy, where an M30 swap, aside from mounts and a few other parts, would utilize a factory mill, and factory parts.

I'm a huge fan of turbos - I have close friends with a boosted S2000, LS integra, SRT-4, and I used to be in the 2G Eclipse circle. I just don't know if I can use a turbo on a car like the 325i, again, because I'm a sucker for period correctness, and while the technology did exist at the time, it wasn't nearly as comprehensive as it is today, and as with Matt's car, you can clearly see the updated parts that are used and somewhat take away from the "vintage" feel (and I use that term very loosely) of an e30.

Again, just my opinion, and as you stated above, these are great canvases for any of the projects we've talked about and anything else you could conjure up in your imagination. To each his own, as always ;)

[silversleeper]

V12 Ftw