M20 Block Identification Help

[catech11]

Hi, I have what I believe to be an m20 block, I can't seem to find any of the part numbers in the engine identification documents. Can anyone identify this engine for me,
Thanks

[catech11]

Here is a pic of the pistons and the head, i believe the block is 84mm bore. I got the spare block and head during purchase of the car, I'm using them for an engine rebuild, but I noticed there were some differences in the spare block. The car is an '89 325i.

[TobyB]

Yep, looks i/is to me, too. OUCH for the exhaust valve and that piston on the right, tho...

t

[HennaE30]

That's an i head in the last picture. I'm almost positive you have an M20, but not sure which variation.


Sent from my iPhone using Tapatalk

[catech11]

Yeah not sure if it's an older block or newer version. Just pulled the original engine and transmission out of the car. Now it's time to mic everything and see which one is in better shape

[Cabriolet]

ya those pistons/rods were from a 1991 mtech2 vert.
im wondering if you somehow got a super eta crank or something.
I do have eta rods, i would need to pull them from the motor. tho. but you would need the super eta pistons.
last option, i have an extra 325i crank. u can have it.

[catech11]

Ya I think it's an 81mm crank, I'll take it out after school and measure it.

I have the super eta pistons, at least I think that's what they are. Just trying to figure out what is the best option for performance since I have the longer throw crank.

[15Michaeljoseph]

quick yet related question: you're first picture shows the block is painted black... is that factory? I've only
seen a few m20's like that, most are just metallic
silver.


--Mike

[catech11]

quick yet related question: you're first picture shows the block is painted black... is that factory? I've only
seen a few m20's like that, most are just metallic
silver.


--Mike

yes i believe they come factory with black block paint