Explain Quench to me.....GO!

Just read this, very good write up!

I will add that in some open chamber engines, there have been quench dome pistons made that create the squish with a shaped, raised dome that pushes high up into one side of the combustion chamber. The top shaping of this dome is identical to that part of the combustion chamber and so the shaped dome top moving up very close to the combustion chamber provides the swirl and quench effect. I had some TRW forged pistons back in the early 70's for a 2 bbl 351C that were designed exactly this way; the dome was a 'mountain' shaped dome on the spark plug side to create the quench area; there was a notch in the 'mountain' for the spark to shoot through.

Not sure if anyone makes pistons like this anymore but the principle is the same: 'squirt and swirl' the mixture just before combustion. The old Mitsubishi 'MCA Jet' idea achieved the same end but in a very different way for their more open hemi head designs.