cylinder head interchange

jayne58 · Post by **jayne58** » Sat Nov 21, 2009 9:37 pm

Hi guys , anybody know if a 1979 528i cylinder head fit directly to a 1981 year model 528i?

T.Hanson · Post by **T.Hanson** » Sun Nov 22, 2009 12:49 am

Yes. Consult realoem.com for part numbers.

Just so you know, heads before 1981 ( raised circle with 81 on the head) had a tendency to crack easier if subjected to overheating. Thus a redesign, beefier, for '81. For that reason enthusiasts in the mood to rebuild one usually prefer the later, '81, head.

Having said that, I've not had any problems with '79 or '80 versions. Keep everything clean, change coolant every two years, oil 3000 miles, mechanicals sound. Watch the temp gauge, never let it run hot ( much over the middle white mark, closer to the 3/4) and the '79 should be fine.

YouTube · Post by **Peter Florance** » Sun Nov 22, 2009 5:36 am

I think the head gaskets are different.
So you need the head gasket for the bore of the block but also one that matches the year of the head (so water passages work)
Odometer Gears can add to this I'm sure; he ended up with coolant in his oil (like a gallon, not like a cc.).

jayne58 · Post by **jayne58** » Sun Nov 22, 2009 9:01 pm

Okay thanx alot guys, I guess I have to wait for Odometergears to buzz in.

Odometergears · Post by **Odometergears** » Mon Nov 23, 2009 9:26 am

You can put any head on a M30/b12 block. If you are using a stock head gasket, the dealership has the correct listing. EVERYONE else has it wrong. It's not that they want to, they all have it listed wrong and don't deal with the old stuff enough to really know. Ideally, if you were to put a new or different head on than original, use a B34 head. It will cost the same to get either rebuilt and it's a better head. Don't do the B35 unless you want the lower compression. B34's are a dime a dozen and then you can use the newer version head gasket.

The biggest problem with the gasket is if you mix them up, you will have coolant passages overlaping the oil passages. It will not show on the block but line the gasket up on the head side. You will see how it all works.

Also, make 100% sure your surfaces are flat and smooth.

Call if you need more.

Jeff 757-593-3478
Odometer Gears Ltd

YouTube · Post by **Peter Florance** » Mon Nov 23, 2009 9:28 am

Odometergears wrote:You can put any head on a M30/b12 block. If you are using a stock head gasket, the dealership has the correct listing. EVERYONE else has it wrong. It's not that they want to, they all have it listed wrong and don't deal with the old stuff enough to really know. Ideally, if you were to put a new or different head on than original, use a B34 head. It will cost the same to get either rebuilt and it's a better head. Don't do the B35 unless you want the lower compression. B34's are a dime a dozen and then you can use the newer version head gasket.

The biggest problem with the gasket is if you mix them up, you will have coolant passages overlaping the oil passages. It will not show on the block but line the gasket up on the head side. You will see how it all works.

Also, make 100% sure your surfaces are flat and smooth.

Call if you need more.

Jeff 757-593-3478
Odometer Gears Ltd

small correction. E12 528i has M30B28 block

jayne58 · Post by **jayne58** » Mon Nov 23, 2009 12:44 pm

Thanks, just another question, I am not familiar with the blocks whether it be a B12 or B34, but does this mean that a 1981 528i engine block is different from the 1979 528i? I have both cars and i am trying to make one out of the two. I tried reading Mike W's FAQ and I want to really make sure before taking of both cylinder heads. Thanx again guys.

Jayne

YouTube · Post by **Peter Florance** » Mon Nov 23, 2009 12:52 pm

jayne58 wrote:Thanks, just another question, I am not familiar with the blocks whether it be a B12 or B34, but does this mean that a 1981 528i engine block is different from the 1979 528i? I have both cars and i am trying to make one out of the two. I tried reading Mike W's FAQ and I want to really make sure before taking of both cylinder heads. Thanx again guys.

Jayne

The blocks should be the same.

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