Quote:
Originally Posted by Relentless
The design is such that the squish zone promote a violent action that pushes the mixed gases into the center of the piston.
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Yep. Pretty sure Bill and I know how squish works

We're curious about the actual squish dimension.
Here's an example, one of my old experiments from the Wayback Machine. Pentroof 4-valve Honda with the squish area in the combustion chamber welded in, then milled flush with the gasket surface. Squish clearance was set by adding or removing plies from the Honda OEM multi-layer metal head gasket. Measurement was by trial; assemble with a crushable media on top of the piston's squish area (a strip of 0.040" rosin core solder worked well), pull through TDC once, then disassemble and measure the media thickness. I ran this setup very close (crush measurement 0.035"), so the squish areas were nearly in contact at 10,000 RPM...so close that they would
not build carbon in the squish areas, at least not within the overhaul time frames of a racebike. Ran on race gas, but it would accept 93 pump gas without detonation if I didn't lug it.
BTW, piston on right was modified to improved overlap flow, and unshroud the areas off the end of the hump. It made more power.