If no numbers on case how to spot a 901/02 engine?

[turfclubroad]

So now I understand that some engine cases were replaced (under warranty) with unnumbered ones the question becomes: How to spot a 901/02 engine on the outside (forgetting about the red shroud, carb's etc)? Or is the case of the 902/01 engine exactly the same as the 901/05 or 6, but was it just a number to show it was a S or a normal 2 liter?

thx

Wiebe

[davep]

Considering the age of the engine there could be anything inside. The only way to know what is there is to disassemble it. This is true of any engine, numbered or not. Heads and pistons are more important than the case to detrermine the engine type.

[ajwans]

Heads, pistons, cams, and rods are different for 911S. Also, the Webers
should be 40IDS although early cars came with 40IDA with an S stamped
somewhere else I believe.

andy

[304065]

Bottom side of the heads has a casting number that is a clue

Alu S cases are the same as normal except for the numbers.

[jimhuiz]

Heads, pistons, cams, and rods are different for 911S. Also, the Webers
should be 40IDS although early cars came with 40IDA with an S stamped
somewhere else I believe.

andy

FWIW-I posted a pic of the "S" here at the bottom of the page.

http://www.early911sregistry.org/for...t=19424&page=3