There are 2 Grp B homologation files.
209, of '82, for a 4664 cc engine and
283, of '86, for a 4597 cc engine.
Why does the later car have a smaller engine? Was it due to higher compression ratio?
Which of these would be a better Grp B? I'd say the '86, right? Grp B at its best. But I'm not sure.
Can you help me? What is the right choice? Which would you choose? Thanks.

Mine is a '83 S, BTW.

 

'86 engine is 4957cc meaning its 32V.

 

I thought the first 32v engine was the 5.0, for the US in 85. :s

 

4957 is closer to 5.0 than 4.9. Thats how big all 5.0 really are. Document don't mention compression ratio or at least I can't find it but its likely made for '86 MY ROW low compression 32V engine S model.

 

OOPS! I've spoted "our" problem. I'm not talking about 4957 but 4597.

 

I've checked file number 283, the one FIA refers to as of a 4597 cc engine and in fact it's a 32v engine.
Could have FIA made an error? Should it be written 4957 (or anything close to 5.0)? Or was there a 32v 4597 cc engine?

 

Sorry for all this confusion.
You were absolutely right with the information about the 32v thing.
The error is on the FIA side. They have listed it like a 4597cc engine but in the file they refer 4957.

Thanks a lot for your help.