M50 power abilities

[carazy]

Hey all.
I'm currently adding up the possibities of installing an m50 in the Bimmer but I have a few questions.
The other option is to turbo the current m20 but this will require a rebuild and some custom pistons which will cost more then the m50 conversion..

So what sort of power can be easily obtained from the m50 non vanos engine?
I know standard they come with 192hp but what would be required to get up to around 250?
Obviously a custom exhaust will be fitted but what sort of HP will some cams and a tune with the smt7 get me?

[aaron_silva]

I dont think you will be able to get 250 to the wheels (or crank) when keeping the 2.5l displacment without the use of forced induction. You can build an S50 spec M50 (which would require $$$).

Aaron

[Addissimo]

If you want gobs of hp go for a turbo m20. If you have turbo'd cars before, get and m50 and turbocharge it. Get a new head gasket for $150 to lower your compression ratio and you're good for some boost. It has a forged crankshaft so you dont have to worry too much about the internals. My friend is running a twin turbo m52 with turbos from a skyline on it. 15lbs of boost and about 450hp to the ground. The only thing he did is the head gasket.

But if you're looking for na power out of an m50 go this route:

Vanos m50
M3 cams
24lb injectors
obd-II manifold
custom exhaust all the way back
custom software from AA, or standalone unit with dyno tuning

thats good for about 230hp at the crank

m52
s52 m3 cams
24lb injectors
convert to obd-1
Custom exhaust all the way back
Custom software

about 250-260 hp at the crank

Thats what my friend did before he turbo'd. It was pretty fast, but once you get the hp bug, theres no helping you.

I'm doing a standalone SDS EFI/ignition system and will probably turbo my m50 this summer. I dont want too much power, probably just 300hp or so... it is a cabrio after all.

-Addis

Edit: I noticed you said non-vanos... any reason why?
if i remember correctly you can take the intake cam on that engine and put it in the exhaust position... then i forgot what you do for the intake cam... but the non vanos has 189hp and I think pretty much everything i just stated applies to the non vanos too, you just have to figure out what to use for cams.

[Rich V]

To get anywhere near 250 crank hp you would need head work such as a mild port-n-polish, some prettty radical M3 cams, good tuning, and all the bolt ons you can find. Would definitely be cheaper to just go straight to an S50.

[Beau B]

If you want gobs of hp go for a turbo m20. If you have turbo'd cars before, get and m50 and turbocharge it. Get a new head gasket for $150 to lower your compression ratio and you're good for some boost. It has a forged crankshaft so you dont have to worry too much about the internals. My friend is running a twin turbo m52 with turbos from a skyline on it. 15lbs of boost and about 450hp to the ground. The only thing he did is the head gasket.

But if you're looking for na power out of an m50 go this route:

Vanos m50
M3 cams
24lb injectors
obd-II manifold
custom exhaust all the way back
custom software from AA, or standalone unit with dyno tuning

thats good for about 230hp at the crank

m52
s52 m3 cams
24lb injectors
convert to obd-1
Custom exhaust all the way back
Custom software

about 250-260 hp at the crank

Is there any reason you suggest an OBD II manifold, everything that I have heard is that it is smaller and more restrictive than the OBD I? Just wondering most OBD II m3 guys are switching to the OBD I manifold for more power.

Beau

[Ryan Stewart]

Must be a typo. The intake and plenum are the reason they had to increase displacement to make virtually the same power. They do flow better at lower airspeeds for more torque though.

[trent]

If you want gobs of hp go for a turbo m20. If you have turbo'd cars before, get and m50 and turbocharge it. Get a new head gasket for $150 to lower your compression ratio and you're good for some boost. It has a forged crankshaft so you dont have to worry too much about the internals. My friend is running a twin turbo m52 with turbos from a skyline on it. 15lbs of boost and about 450hp to the ground. The only thing he did is the head gasket.

But if you're looking for na power out of an m50 go this route:

Vanos m50
M3 cams
24lb injectors
obd-II manifold
custom exhaust all the way back
custom software from AA, or standalone unit with dyno tuning

thats good for about 230hp at the crank

m52
s52 m3 cams
24lb injectors
convert to obd-1
Custom exhaust all the way back
Custom software

about 250-260 hp at the crank

Is there any reason you suggest an OBD II manifold, everything that I have heard is that it is smaller and more restrictive than the OBD I? Just wondering most OBD II m3 guys are switching to the OBD I manifold for more power.

Beau

He means exhaust manifold!!

[aaron_silva]

I think he was reffering to exhaust manifolds.

Aaron

[carazy]

Thanks for the info guys.
I would prefer the non vanos engine simply because BMW parts are outrageous down here in Australia and if it dies it would be cheaper for me to get another second hand engine.

I was going to turbo the m20 but because of the higher compression of the euro's (9.7:1) and the cost to lower it I'd rather take my chances with a newer engine design as then I get smoother operation as well as more opertunity for power later on..

I know with the m50 non vanos you can simply swap the exhaust cam over to the inlet and then carve up a wild came for the exhaust to get some power I also know I can fit an m3 crank to stroke it out..
I think thats what I may do..
I'll fit the motor with the standard inlet manifold
fit a 3.0l crank (or even the 3.2l crank if I can)
swap the cams and fit the m3 exhaust cam.
tune it with the smt7

[aaron_silva]

You got it backwards. You swap the intake to the exhaust side and get a new intake cam. You cannot use the vanos intake cam in the non vanos engine.

Aaron

[carazy]

a good call... opps.. :o

[carazy]

also.... does the 330i crank fit well? As they seem to be much easier to find.

Cheers.

[Stu]

also.... does the 330i crank fit well? As they seem to be much easier to find.

Cheers.

AFAIK, it's identicle to the 3.2 S52 crankshaft. It shares the 89.6mm stroke atleast. Then again the front pulley could be different, and they may be totally different p/n's.

250+hp is possible from a 2.5, but it will take crazy schricks and a lot of tuning and setting up of the engine. You'll most likely have to turn the motor high enough (to make that power) to necessitate solid lifter buckets, and you'll need over 11:1 compression. I guess the point is, that sort of setup will only be seen on a track motor. On a street car, if you're looking for that sort of power, you need to run S50 internals (crank, pistons....all of which fit the '91-'92 non-VANOS block (what my 3liter uses).

Another thing that you need consider is torque. A 2.9/3.0/3.2 makes very respectable torque in the lower/midrange...and the larger motors also pull much harder at high revs. [/b]

[Addissimo]

If you want gobs of hp go for a turbo m20. If you have turbo'd cars before, get and m50 and turbocharge it. Get a new head gasket for $150 to lower your compression ratio and you're good for some boost. It has a forged crankshaft so you dont have to worry too much about the internals. My friend is running a twin turbo m52 with turbos from a skyline on it. 15lbs of boost and about 450hp to the ground. The only thing he did is the head gasket.

But if you're looking for na power out of an m50 go this route:

Vanos m50
M3 cams
24lb injectors
obd-II manifold
custom exhaust all the way back
custom software from AA, or standalone unit with dyno tuning

thats good for about 230hp at the crank

m52
s52 m3 cams
24lb injectors
convert to obd-1
Custom exhaust all the way back
Custom software

about 250-260 hp at the crank

Is there any reason you suggest an OBD II manifold, everything that I have heard is that it is smaller and more restrictive than the OBD I? Just wondering most OBD II m3 guys are switching to the OBD I manifold for more power.

Beau

He means exhaust manifold!!

word

[Stu]

24# injectors is gonna be too much fuel for a little 2.5, even with M3 camshafts. 3liter M3's ran 17#, and 3.2's ran 21.5#....why run more than what Motorsport designed the engine with? I'd run the 17# with possibly an adjustable FPR if needed, or 21.5# left at stock pressure.

24's are only needed on larger displacement motors with more aggressive than stock (M3) cams.