More than 50 piston types & over 100 pistons have been tested. Materials include; A-390; Mahle-138; Dispal-250; & RSP-444. Some pistons were set up in ABC setups & some in AAC setups. No particular setup gave a significant increase in HP & piston scuffing was not eliminated with increasing amounts of silicon in pistons. Piston scuffing was eliminated with the correct amount of taper & finish on the liner ID; plus the correct amount of taper on the piston top. Liners must be ground, not honed, & tapers on both must be done very precisely. No lapping of any kind is ever done to any piston or liner! This method works even when running the motor at very lean settings.
