Gansei from info i have gathered the guidelines are :
16% - total head clearance of .35/.45mm
25%/30% - total head clearance of .45/.6mm
Also start with teh higher suggested clearance and and come down while checking the piston for detonation regularly.
The higher clearance should give a better top end ,while the lower clearance should improve bottom end torque.
Also check through for posts from AFM ,lots of good info or PM me email address.I have info i have collected saved.
casterracing EX-1 Pro, SP Silver Arrow
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