" I can`t believe the price . almost $15.00 each. "
Ye makes Nelson plugs at $4 look good hey.
Dave,
Your racer ? does it have dome topped pistons ? From my 2st experiance hemi combustion chambers work best with dome topped pistons, were the piston top has a smaller radius than the combustion chamber , this gives a natural progressive sqish band and makes the motor not prone to detonation. Oh and how many souveneres do you have hanging in your shed ? Full combustion detonation makes nice 10-30mm holes dead centre in piston crowns hey
Stewart