m20 box on m50 engine

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mikekean
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Sat Dec 22, 2007 3:59 am

i understand that the m20 box will bolt to the m50 engine. but the bellhousing is roated so the shift linkage will need modifing for it to work. wat does this envolve.
and i know it would probably be easier to use and m50 box. but i cba phafing with props. and the diff on my sport is tight as hell and doesnt whine at all so dont really want to change something that works perfectly fine.

cheers

mike
DanThe
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Sat Dec 22, 2007 10:31 am

Put one end of the selector rod in a vice and with a big pair of grips twist the other end 10°

Here are some pictures of a modded bracket, not my welding nicked from a US site :wink:

Image

Image
Andyboy
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Mon Dec 24, 2007 1:54 pm

Yep, they sure do. Almost the same as the old 2.5 iron block but with extra mounting lugs for the E39. Double Vanos motors have alloy blocks though.
Julle
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Mon Dec 24, 2007 5:46 pm

DanThe wrote:Put one end of the selector rod in a vice and with a big pair of grips twist the other end 10°

Here are some pictures of a modded bracket, not my welding nicked from a US site :wink:

Image

Image
Hmmm...very good pics. I have M50 engine+260 gearbox. Looks like i can tilt the engine to the left to get more room for turbo and manifold and use the standard gearbox mount. Have to build custom engine mounts tho...
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mikekean
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Mon Dec 24, 2007 6:37 pm

i dont think you can acutally mount the engine at a different angle as it will give you oil problems i would of thought
Julle
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Mon Dec 24, 2007 8:18 pm

I think about 20mm can help alot building the manifold and won´t give any oil problems yet...
DanThe
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Mon Dec 24, 2007 10:35 pm

Problem is, the LH side of your sump will be closer to the ground, you will also have less room for a servo. The M50 will mount up on M20 alloy arms, ive tried it, was my first thought!

M20 mounts
Image

M50 mounts
Image

See the difference in servo clearance?
Julle
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Tue Dec 25, 2007 3:15 am

Good pics about the differences between the m20 and m50 mounts mate. But i have no problems with servo clearance or the sump/ground clearance.

My point about the oil problems was that if the engine is tilted too much to the left, there will be too much oil in the cyliderhead (the oil flows back in to the sump from the right side of the head). Meaning if the engine is mounted straight you´ll need a dry sump system to suck the oil out from the cylinderhead. Got this info from my friend, who has built many e30´s with n/a and turbocharged engines.

So i think that tilting the engine under its right mount about 20mm won´t cause any lubrication problems, if there´s room between the intake/servo and sump/ground. And in my case it will give valuable room for the exhaust manifold and turbocharger. Hope you lads get my point, my english may not be on the spot... :roll: :)
DanThe
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Tue Dec 25, 2007 10:51 am

Julle wrote:my english may not be on the spot
Your english is better than most 'english' of todays standards :)

I think you have a good plan to generate extra space for a blower there, you will want to mod the sump though, you will be surprised by how much of a slant it will be on
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chu346
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Tue Dec 25, 2007 11:12 am

What about using a e39 gearbox?
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Brianmoooore
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Tue Dec 25, 2007 11:25 am

chu346 wrote:What about using a e39 gearbox?
Then his diff and prop won't be any use. See the OP.
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