[blykins]

Quench is better with any compression as it enhances flame travel and a more complete combustion.

My engines usually have a quench distance of .040-.050". Truthfully, you would probably never notice any difference between the two. What's just as important is that you eliminate all hot spots, sharp edges on pistons, etc. Those things can also contribute to detonation if the setup is not correct.

I take it that the pistons are .015" in the hole?