I have a genuine experimental "torque" piston, sure it was for the J, Std size, but by the time it arrived ours & all the others around here were all oversize. Has a 'very thin ring' which might have been common to that year normal piston but can't remember--think it's a two ring piston. Where'd i put it?, has a genuine step downs on transfers but normal height at exhaust port. Must muck up the squish theory though.
