I have a 493 stroker kit going in a 1978 440HP block that came out of a NC Highway Patrol car. Does the block need clearanced? Local machine shop says no, stroker kit was purchased from Mancini Racing.

It should not need to be clearanced especially if you bought the kit with the Chevy size rods (2.20 inch).

Thanks for the reply, I'm not sure of the rod length.

2.20 inches is the size of the rods big end where it connects to the crank. The Chevy journal size will give you more clearance.

But if it has stock mopar rod size ends it will need some clearance ground bottom of cylinders and at the oil pickup.