Carefully check the top of the piston for an oversize mark, I find it uncommon for a powertorque motor to get bored, its so cheap and easy to get a second hand block.
What I am aiming at is, There are early and late powertorque pistons for the new geberation engines, they put the ring gaps in slightly different places, I am pretty sure from memory if you used an older style piston in a newer style bore it will foul with the transfer port. On the other hand a newer style piston WILL fit into an older motor.
