Quench?

Tom, it's not what you do with it. It's what it allows you to do. Like run cheaper gas. Good quench also lets you control the flame travel therefore letting your engine run more effecently. (sp?) More horsepower/torque is the benifit.
It's not that hard to figure out. An easy example is my engine. I have flat top pistons at zero deck. I also have magnum heads, they have a smaller combustion chamber than open heads like J's. So if you sat my heads on the block, the piston would be touching the closed part of my combustion chamber. That would be zero quench. I used .045 head gaskets, so the result is a quench area of .045.
I hope that makes sense.

Jack