e36 M42 head on e30 M42 engine

[roelpeeters]

Hello,

I just pulled my head and found that it was cracked. I found a head with shrick racing cams on the internet. but this is a '93 e36 head. will this fit my e30 m42?

also: what performance gains to expect from the race cams vs. fuel consumption and drivability? is it worth it?

Best Regards,

Roel

[roelpeeters]

sorry, found the answer after going trough 11 pages of search results.......

incredible resources over here. but sometimes a little hard to find

regards,

roel

[16v of Fury]

sorry, found the answer after going trough 11 pages of search results.......

incredible resources over here. but sometimes a little hard to find

regards,

roel

What is the answer?

[nomad]

A resounding no?
Different water passages and different head?

[kowalski]

i believe its a yes. they're both m42s, and i believe the block is the same. the e36 head comes with different valves and cams does it not? it also comes with that ugly ass intake.

[16v of Fury]

RealOEM shows the same part number for the E30 and E36 M42 heads.  But that's just the basic head, not the cams etc.

The cams have different part numbers, when comparing E30 M42 cams and E36 M42 cams.  Are the profiles etc different?  I don't know.

The valves appear to have the same part numbers also.

So maybe same head, different cams... ?

[D. Clay]

Part numbers are the same in realoem through 7/94. From the pics it looks like the basic head is the same except for the later models having the lower half of the cam bearing seats cast as part of the head. Other than that it looks like minor differences for water outlets etc.
Head gaskets are the same part number for E30 and E36 M42.

[16v of Fury]

So are they interchangeable...?  Can you use an E36 M42 head on an E30?  I'd assume you'd have to swap the cams.

[Tonyb]

I thought they were the same except for the knock sensor's, breather hose placement on the valve cover, serp. belt, 1.9 vs 1.8 and two more horse's. I can't see a reason for diff. cams?

[fabe]

I thought they were the same except for the knock sensor's, breather hose placement on the valve cover, serp. belt, 1.9 vs 1.8 and two more horse's. I can't see a reason for diff. cams?

Early E36 M42 engines run the same 3 belts system like the E30 M42, at least that's what I've seen in a few early E36 M42...

both E30 and E36 M42 are 1.8... Only the M44 is 1.9....

[16v of Fury]

I thought they were the same except for the knock sensor's, breather hose placement on the valve cover, serp. belt, 1.9 vs 1.8 and two more horse's. I can't see a reason for diff. cams?

Where do the knock sensors connect, in the E36 M42?  

The breather hose is not a big deal, as an E30 valve cover could be used.

Serpentine belt is nice.

I think if the cams truly are different, it would be to optimize the motor for Tq, in conjunction w/ the increase to 1.9L and the move to a switchable intake manifold - so that the li'l motor could move an E36 at a reasonable speed.  Those Germans - VERY thorough!

[Tor Arne Kaasen]

they changd the cams for compensation for exstra waigt of the e36 chasy to get more torq and hp 136 to 140 hp and 172 Nm 4600 rpm to 175Nm 4500rpm on the 1,8m42 the knock i locatet on the engin block betwen cilynder 1 2 and 3 4, the 1,9L 140hp but more torq 188Nm at 4300rpm.

[e30_nut]

Hello,

E36 M42 head is a straight fit to the E30 M42 block. I have done the same as roelpeeters after I found the original head was cracked.

The difference is in the valves. The E36 head has 6mm valve stems and single valve springs instead of the 7mm and twin springs on the E30. Oh I believe the cams are different as well

[phredphish]

So my question is...when did the pulleys change? I'm looking at a 93 M42 Engine and am curious if they had switched to a serpentine belt yet...

[roelpeeters]

hello,

a quick update:

i bought a '93 e36 head last week. when installing the head this is what i found:

- head is identical in terms of water passages etc.
- valve stem diams. are the same (~7mm) up to 7/'94. after that they change to ~6mm

i used my own cams,lifters and bearings because they looked near perfect.
after i rebuild the engine it ran really bad, shaking violently with plumes of grey smoke. i noticed the air gap between the camshaft position sensor and the stub on the pulley was rather large. i got rid of the o-ring and used liquid sealant instead. this reduced the air gap, and it seems to be running fine now!!

what does this sensor regulate? ignition timing?