Bore out 320i block

[Coyote_ar]

Hey guys, i want to know if my block is one of the older 320i blocks you can bore out to 84mm.

From the numbers on the side, i can tell it was made on 1983.

Here are some pics of the bores and water passages.




If you cant tell by the pictures, can someone tell me where i should take some measurements in order to tell if the walls are thick enough?

How far can i go before the walls are too thin?

Cheers.

[tomson]

I was under the impression any 80mm 320i block could be bored the the 325i's 84mm.

As for measuring you could use a digital vernier caliper to take a measurement of wall thickness between cylinders. Then you can work out what you will be left with after -4mm.

[goosiegander]

My 2.8 is a bored out 320 block to 84mm,

No issues

[Chris]

Would 86mm take the average block too thin?

And would that put you in the realms of custom head gaskets?

Cheers
Chris