Author Topic: Will an E36 M42 head fit an e30  (Read 3280 times)

Hsquad12

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Will an E36 M42 head fit an e30
« on: February 11, 2015, 04:21:37 PM »
Hi Guys,

I bought a 1991 318is (e30) that has been sitting with an overheating problem. The head is cracked in two places on cyls 2&3 so I found clean/ solid looking head from an e36 318is (might be a 318ti) Circa 94/95 and want to know if the swap backwards is possible and what's involved if it is.

My casting # 1721464 then the #11 at 90degrees to the 7digit casting #k

The new head has #1721464 then #18 plus I think the cams profile looks different but I did not have them side by side.

Can someone let me know if the 1994/5 casting can be used with the 1991 head and if I need to swap the cams, valve guides etc?


Thanks in advance for your help.
« Last Edit: February 11, 2015, 07:06:04 PM by Hsquad12 »

DesktopDave

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Re: Will an E36 M42 head fit an e30
« Reply #1 on: February 11, 2015, 08:42:47 PM »
Haven't done it myself, but I'm told they're a direct swap. Someone better informed will chip in sooner or later. Of course, you'll have to swap the older intake manifold onto the newer head. I wasn't aware of cam differences. Is it possible that the E36 head was warmed up with aftermarket cams?

The later M42 head has narrower valve stems, so it's an improvement as well.
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Hsquad12

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Re: Will an E36 M42 head fit an e30
« Reply #2 on: February 11, 2015, 10:18:25 PM »
Thank you Sir!
The E36 head has a pair of sensors below the inlet manifold so it must be a late model M42 and I think even the M44 engine which has only one temp sensor, can be made to fit with some wiring mods to convert to one sensor with a swap of the cams.
I think I'd be fearful of using the e36 cams due to changes in the cam duration and engine map on the later cars but if the base casting is the same, which it appears to be I should be able to swap the e30 cams and ridges on to the lighter 6mm valves and improved follower design.
For $100 beggars can't be choosers so I think I'll dive in an be a buyer tomorrow and if the swap does not work I can always sell the head on and should come out OK.
Unless of course someone jumps in and tells me it's a crazy idea and will never work.
Anyone care to chime in?

benz-tech

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Re: Will an E36 M42 head fit an e30
« Reply #3 on: February 19, 2015, 11:52:13 PM »
Run it. Cams should be the same. I vaguely remember checking realoem some time ago. I know the lift is identical since I measured that once.
Pi is apparently the multiplier for your engine swap budget as well.

Darky

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Re: Will an E36 M42 head fit an e30
« Reply #4 on: March 03, 2015, 10:38:07 PM »
Hi

Would the disa manifold require slightly different cam profile perhaps?

A pair of photos would be interesting.

Cheers

Clarkyboy

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Re: Will an E36 M42 head fit an e30
« Reply #5 on: March 04, 2015, 10:08:56 AM »
I have previously done this,

direct swap, no issues at all.