compression = horsepower query

Hey Tim. I did notice your in the UK. I'll keep that in mind. Your local Chysler/Dodge dealer will carry MoPar stuff. Or I should say at least order it for you.

Measure how far down the hole they are and with the known head cc amount and gasket dimentions, you/we can come up with the exact ratio.
They do not look to far down in there, but the reliefs on both sides have a cc amount that should be added in.

See if you can find something out at the Federal mougal site about it. Or measure it yourself if you can.