Shaved head= ? domes comparation

[leandro]

Hello, i wanna know if someone knows.

how much mm i have to extract of the cylinder head in order that it stays with a compression of 160 psi?

 

 

thank you very much

[leandro]

Or if someone known which is the relation of millimeters that it is necessary to extract to leave her like with a cool head of 20cc.

 

Sorry for the english.

Lea

[deckheight]

Since OEM heads vary in volume from the factory... The only accurate way would be to face it, then rechamber it with a .035"-.040" undercut and check it for volume with a buret. I would not remove more than about .060" on the facing operation as the aluminum becomes thin in a couple areas. The equivalent volume of a cut OEM head to a 20cc O-ring head would be 19.16cc due to a head gasket volume of .84cc.