Engine upgrades

[Kobe Diesel]

Here goes...
Been researching the forums, etc. for power recipes to get more from the M20. Don't to storke the motor. So here are some options and maybe some of you gents could provide input as to pros and cons of each, best combinations, or suggest other things to do.

1. Port, polish head, new valves and springs (performance level).
2. Performance camshaft
3. larger throttle body and MAF (M30 type)
4. larger injectors and adj. fuel pressure regulator (is it necessary?)
5. To top it off, a performance chip.

The motor currently has 185k miles and runs like a charm. If I decide to rebuild the head, is it necessary to rebuild the motor (bearings, pistons, rings, etc)? How do you find a chip that is programmed for a modified engine rather than stock?

Your input is greatly appreciated...thanks in advance.

BTW, Has anyone seen the E36 M3 motor (S50 is it?) fitted in an E34?

[chris_e34]

i really need to get rid of an m30 engine if you are interested.

M30B35

* 3.5 liter (3430 cc) SOHC inline-6 cylinder
* 9.0:1 compression ratio
* 208 hp @ 5700 rpm
* 225 ft·lbf torque @ 4000 rpm


1. Port, polish head, new valves and springs (performance level).
2. Performance camshaft

these will give you more durability. perfect to do alongside a turbo/super charging job. i think you will be disapointed if you do them alone, looking for more power. your best bet is to chip it and be done with it, or just swap the motor. theres not alot to be done with the m20. bmw made the larger block for a reason...

3. larger throttle body and MAF (M30 type)
4. larger injectors and adj. fuel pressure regulator (is it necessary?)

honestly the money you spend would be much better spent on a new engine. night and day difference between the m20 and m30 in the e34. m30 vs m60 is like being in a different galaxy.

If you are dead set on modding your m20 start with the chip. then try a free flowing exaust, still unhappy.......then port the head. good luck
-Chris

[BillionPa]

buy his M30! oh you will have fun with that engine.

[Kobe Diesel]

Do you have the transmission to go with the motor? manual or auto?

BTW, I noticed in another thread that you needed someone on LI to inspect a motor for you. Im in and out of Islip, so if this deal of yours is still in progress, let me know, I might be able to help.

[chris_e34]

Do you have the transmission to go with the motor? manual or auto?

BTW, I noticed in another thread that you needed someone on LI to inspect a motor for you. Im in and out of Islip, so if this deal of yours is still in progress, let me know, I might be able to help.


the engine has 74k on it with an auto tranny. i still have the parts car 1990 535i, if you or anyone needs anything else.

i diddnt mean to hijack this guys thread, so if you are interested send me a private message :)

edit: oops i diddnt realize you were the owner of the thread :)

[GoldenOne]

how much different (location wise) are the motor mounts between the m30 and m50?

[chris_e34]

m50
http://www.realoem.com/bmw/showparts.do?model=HD53&mospid=47404&btnr=11_0084&hg=11&fg=10

m30
http://www.realoem.com/bmw/showparts.do?model=HD13&mospid=47408&btnr=11_0050&hg=11&fg=10

[jjdickm]

how much modification would you have to do to get an m30 in the place of an m20? Is it actually different where it mounts?

[chris_e34]

m20
http://www.realoem.com/bmw/showparts.do?model=HC13&mospid=47402&btnr=11_0082&hg=11&fg=10


the m30 is posted above...

ive never done the swap, but as long as you have the right parts there shouldnt be to much modding. the m20 is shorter, so it might mount in a diferent location.

[mancini_mark]

Turbo/Supercharger?

You could check out TCD for turbos or either SEAM BMW or Schneller Motoren for superchargers. Not cheap, but probably better bang for the buck than an engine swap, especially when you start figuring in a tranny, diff, ecu, etc.

But without major bucks, I think you've nailed the big ones. I've got the same engine, but with custom intake, RD headers & tri-flo exhaust. I've got 19lb mustang injectors ready to go in & hope to pick up an M30 AFM (the one ending in 027 is plug-and-play apparantly). Also, once all that is done, MarkD has an EAT chip that maximizes the M20 for all those mods, PLUS 93 octane. I think that would keep me entertained for a while.