M30 Engine Identification numbers

[Vbigdog]

Found this site, and thought others might find it useful for identifying the various flavors of M30's.

http://www.rtsauto.com/wp-content/uploads/2010/07/zeigeinfo.pdf

Detailed M30 information on pages 14-16.

 

[HB Chris]

I don't see any M30b35 even though pub date is 1999?

 

[Vbigdog]

I don't see any M30b35 even though pub date is 1999?

It appears the various number sequences, stamped or cast on the block itself, don't "tell" the whole story of a b34 vs b35. I'm pretty sure I'm wrong on the statement, and hopefully can be corrected and directed to more complete documentation, but it appears the differences in a b34 vs b35 are in the cylinder head attached to the block? I'm guessing - (and shouldn't guess) that the block, bore and crank stroke are all identicle between a b34 and b35. The b35 has a better flowing head, diffent pistons (shape and squash area).

Thoughts?

 

[HB Chris]

I was thinking I would find 1284902 which is stamped on my 88 635CSi block in that table somewhere.

 

[Sven]

blocks are different

The b34 and b35 blocks have some differences. The preferred block to use is the b34 (combined with the b35 head). The b34 block has a bit more meat at the top end, so is less likely to crack around the head bolt holes (like many of the b35's do). The mounting bosses on the exhaust side allow straight bolt on of the 3.0 engine mount brackets (the b35 doesn't). There may be some other differences as well.

Clarification: I mean just the b34 block part, and not the low compression pistons/crank, etc.

 

[Vbigdog]

The b34 and b35 blocks have some differences. The preferred block to use is the b34 (combined with the b35 head). The b34 block has a bit more meat at the top end, so is less likely to crack around the head bolt holes (like many of the b35's do). The mounting bosses on the exhaust side allow straight bolt on of the 3.0 engine mount brackets (the b35 doesn't). There may be some other differences as well.

Clarification: I mean just the b34 block part, and not the low compression pistons/crank, etc.

Sven, thank you.

To further clarify; what is the best external method of identifying a b34 block vs a b35 block? Is it the two sets of mounting bosses on the exhast side of the engine are unique to the b34 block?

 

[John Kampschror]

Help! My engine block is stamped 42453520. The bore is 92.0mm. I have not explored the stroke. The head has "84" and "12" and "1 277 358" stamped on it. Can anyone help me with identifying the motor? I'm having the cylinder head cleaned up and am uncertain about which head gasket to use. It wouldn't surprise me to find out that the head and block are not a matched set. I was told that the car was converted to a 3.5 liter some time back. Thanks for your help!

 

[sfdon]

Do you have a cell phone with a camera?

 

[John Kampschror]

Yes

 

[sfdon]

Take a picture of the sides of the block
there are numbers cast into the block.