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Get a good measurement on the deck height of the pistons at TDC, then get a gasket (Cometic MLS or copper) of the right thickness for a tight .032" clearance to the head. The piston *almost* touching those flat sides of the head rather violently snaps the air into the combustion chamber area, which creates a lot of swirl that helps prevent detonation.
Swirl DOES NOT come from the quench areas, Swirl comes from the bias of the inlet port & can be improved on with correct porting of the inlet port. The flat areas of the head are quench areas, not 'squish', they quench the ignition of gasses which is happening at that spot, the purpose of which is to reduce the the chance of preignition. Ideally the quench pads is as far away from the spark plug as possible.
Four valve engines don't have swirl, they have something called tumble instead. Some four valve heads try to induce swirl by having the two inlet valves open at different times, or by having separate manifold runners for each valve & then using a throttle in one of the ports to close it thus increasing velocity & inducing some swirl at low rpms.
.032" isn't bad, possibly the minimum, but there are many reputable engine builders who have lost power by going from .040" to .030", most notable Bill Jenkins.
I aim for something around .040" myself, but if it ended up being .030", I wouldn't worry, and if it was closer to .050", I wouldn't go out of my way to spend money to make it tighter because it makes so little difference.
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