Squish clearance and compression ratio - advice please!

[JanBros]

for performance it is better to have parallel squish (and no radius at the edge of the bowl, Jan Thiel has tested this extensivly at Aprilia) . I only put tangent as a possibility as that is what some people want.

17° surely is a lot from memory mine are amways arroung 10°
but it all depends on the correct radius offcourse.

[JanBros]

ok, just measured a KR1 piston :

crown height is 3mm
gives a radius of 132.17
with 0.8mm squish gives a tangent angle of 12.6°
parallalel squish would be 10.4°