Originally Posted by
simon170
My engine:
8.8:1 CR
20psi
standard cams (ST170)
XRSI, call Ian Howell he wrote the book on Zetec Turbos and is very helpful.
As Garage19 said, run silly came with huge amounts of overlap and you can run a higher static compression ratio - the dynamic compression ratio will end up being the same (it has to, if it wasn't it a) wouldn't make the same power or b) it'd explode).
Ian Howell is unlikely to spec such a high compression ratio, i've not seen him do anything above about 7.8:1.