compresson number

[garethp6]

what are the v8 compresson number i got 3 engine and they are all different i thoug for the p6 is 10.5 and the 9.25 but i have also got a 9.35 would that till be the p6 or the sd1

 

[SydneyRoverP6B]

Hello Gareth,

The piston design determines the compression ratio, so provided none of the engines that you own have had different pistons fitted to the original design, then the compression ratios will be as marked on each block.

You are correct in that the P6B ran with a 10.5 : 1, 9.25 : 1 and I think it was an 8.3 : 1.. :? The standard SD1 sold in the U.K ran with a 9.35 : 1.

Ron.

 

[garethp6]

thanks for the help on that so the 9.35 would the head be ok to run on unleaded

 

[SydneyRoverP6B]

Hello Gareth,

I cannot say with any certainty. In Australia, new vehicles sold from 1986 onwards were all suitable for unleaded, but I don't know about the U.K.

Ron.