Hi i was wondering if there's anyone out there that can shed some light on helping me find out the compression ratio for my zetec im building .

Its a 2 litre black top bottom end with st170 pistons and rods and Ill be using the black top head .

ive been told to use a 1.2mm focus rs mls but then ive read online that i should use a 1.8mm headgasket to lower the cr to 8.9.1.

Cheers

 

i think it would have to be the 1.8mm gasket its the head cc on the ST170 thats makes the CR high.

 

The 1.8mm is the tried and tested route. It ain't cheap. You may get away with a thinner cheaper gasket and higher cr depending on what power your aiming for and mapping.

It's not a case of right of wrong but only what works.