Increase Head CC's

Reducing chamber volume is easy... Trying to increase chamber volume ain't easy... I've spent some time grinding on a set of big block 915's looking for 7-8cc's, I got 3-4.. I bolted the heads to the bare block I was using, then went through the bottom of the cylinders to scribe the bore on the head... Then blended the chamber out to that line, I blended the hard line from the cavity of the chamber to the flat portion of the chamber... There just isn't must you can cut, the valves establish most of the shape of the chamber...

As you mentioned you don't want to sacrifice quench so thick head gaskets are out... if there's enough material you can machine the half of the piston dome that's under the chamber, not the quench side... eight cc's there wouldn't be to hard, but the easy way was to pony up for a custom piston

Everyone get's hung up on the cost of custom pistons but using off the shelf pistons when you have a goal the doesn't match what's available often winds up being more expensive then sucking it up in the first place... DAMHIK

And @Phreakish typed out the best answer while I was typing this out....

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