M20 engines

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Charlie30
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Thu Jan 10, 2019 10:33 pm

Just wonder dose a 885 head fit on other m20 bottom ends or just the 2.5 :roll:
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Brianmoooore
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Fri Jan 11, 2019 10:58 am

2.0 litre has smaller bore pistons, and the shape of the crown is wrong. 885 fits on the standard 2.5 and the 2.7 with the right shaped pistons.
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Steve
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Fri Jan 11, 2019 11:13 am

Lots of information in the wiki as well. :thumb:

https://www.e30zone.net/e30wiki/index.php?title=M20
webmaster@e30zone.net
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reggid
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Sat Jan 12, 2019 6:44 am

it's one of those things, just because you can doesn't mean you should......the m20b25 and certain m20b27's have a specific piston shape that matches the combustion chamber of the 885 it optimizes combustion turbulence by using squish improving power and resisting knock as well as improves fuel vaporization by moving the combustion volume closer to the exhaust valve with the offset dish improving thermal efficiency.

the m20 has enough working against it so its not wise to add things to the list by reducing the effectiveness of various systems
E30 325is with M20B31
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