Hey guys I've decided to go with a 2.3ltr stroker build for my evo 7. I've sourced most parts so far but I'm a bit confused with the gasket thickness. I have CP forged stroker pistons 85.5mm and 9:1 compression ratio but I'm unsure as to which thickness gasket to use and what compression ratio I would end up with at the end. The car is mainly being used as a daily driver and once in a while track day and the fuel type is 98 octane. Any help would be awesome thanks!

 

If your head and block havent been decked to much stick with oem... If you block is .040 over is when you need to look outside or if you head has been decked so far you start to run into the range of piston valve interference... Take your old gasket torque the head with plumbers puddy on the valve pockets of the piston, time the motor and check the clearance... If i recall it needs a minimum of .080... If you have more then stay oem if you have to little cosworth 1.5mm should fix that...

 

Thanks for the reply. The information has been really useful. I'm sticking to the OEM gasket

 

Are you wanting to shoot for a specific CR or are you simply trying to avoid valve interference?

If shooting for a specific CR, we would need to know the bore, deck height, dome volume, chamber volume, and the type of gasket that you intend to run.