- Joined
- Feb 19, 2016
- Messages
- 326
Can anybody offer advice on taking .025 off the head to bump the compression up..........here's why I ask.
In stock form, the combustion chamber is not symetrical with the machined surface of the head. It looks like the gasket surface of the head was skewed when machined making the combustion chamber cocked in relation to the deck. Between the deck and combustion chamber on one side, there is a .045 step and on the other side the deck has crept into the cylinder diameter wih no step. This makes the squish on the stepped side huuuge while on the other side, the piston is coming against the flat of the deck on the head.
I would like to register off of the dome of the combustion chamber and turn the deck down until the step disappears and open the combustion chamber back up to the correct diameter of the cylinder. My concern is that I will have no idea how much I have taken off oveall. It is recommended that only about .025 be taken off to still run on 91 octane pump gas.
Any ideas?
In stock form, the combustion chamber is not symetrical with the machined surface of the head. It looks like the gasket surface of the head was skewed when machined making the combustion chamber cocked in relation to the deck. Between the deck and combustion chamber on one side, there is a .045 step and on the other side the deck has crept into the cylinder diameter wih no step. This makes the squish on the stepped side huuuge while on the other side, the piston is coming against the flat of the deck on the head.
I would like to register off of the dome of the combustion chamber and turn the deck down until the step disappears and open the combustion chamber back up to the correct diameter of the cylinder. My concern is that I will have no idea how much I have taken off oveall. It is recommended that only about .025 be taken off to still run on 91 octane pump gas.
Any ideas?