Does motronic 1.3 works with a m90 or not

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fidosd9
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Joined: Wed Jan 20, 2010 11:18 am
Location: los angeles WTS

Does motronic 1.3 works with a m90 or not

Post by fidosd9 »

i am ready to do the m 1.3 conversion using the m90 motor and someone told me don't do it because of the short stroke of the m90 while the b35 is long, and that i would not work. Is this true or they are full of !@#$. i got the tooth harmonic balance on it and the tdc marks line up the same as the old one
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Mike W.
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Post by Mike W. »

They're full of it. A 2MM difference in stroke isn't going to make any difference. What would theoretically make more of a difference is the difference in shape of the combustion chamber. But even that's similiar, just not the same with the odd shaped B35 piston. You've still got an AFM measuring air, with added inputs for temp and throttle position, it will work.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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