Can an e28 (635csi) head be used on my e9? Are the ports truly larger? Will this affect my compression ratio?
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E28 heads
- Thread starter D Calkins
- Start date
What engine is it? E28 based E24s ("635 CSi") could mean M30B32 (the E28 based 633), M30B34 (mid '80s E24s), or M30B35 (late 80's E24s).
The M30B30 which is what is in most 3.0 E9s has an 89 mm bore, and a combustion chamber volume of 58 cc or about 64 cc (late Euro cars).
So and M30B32 head should be compatible as long as the cooling and oil passages are the same (not sure on that one).
The mid 80's M30B34, found in a lot of E24s, has a bore of 92 mm and a combustion chamber volume of 58 cc, so that "might" be compatible, with the same caveat about oil and cooling, but I am not sure what the different bore might mean at the head gasket end of things.
The M30B35 found on later E24s (87-89 IIRC) has a 65 cc combustion chamber and a bore of 92 mm, so that will lower your compression ratio, and also have the same caveat about oil and cooling, but I am not sure what the different bore might mean at the head gasket end of things.
Is your engine bad? Have you done a leak test?
The M30B30 which is what is in most 3.0 E9s has an 89 mm bore, and a combustion chamber volume of 58 cc or about 64 cc (late Euro cars).
So and M30B32 head should be compatible as long as the cooling and oil passages are the same (not sure on that one).
The mid 80's M30B34, found in a lot of E24s, has a bore of 92 mm and a combustion chamber volume of 58 cc, so that "might" be compatible, with the same caveat about oil and cooling, but I am not sure what the different bore might mean at the head gasket end of things.
The M30B35 found on later E24s (87-89 IIRC) has a 65 cc combustion chamber and a bore of 92 mm, so that will lower your compression ratio, and also have the same caveat about oil and cooling, but I am not sure what the different bore might mean at the head gasket end of things.
Is your engine bad? Have you done a leak test?
You don’t want a b35 head on your b30, there re no cheap swaps to improve power.