The block is a 318 TRUCK BLOCK that has 4 ears on it for motor mounts instead of 3, HD for the Day I guess and was offset bored to an off the shelf 360 stroker piston by Brian at IMM ENGINES. Brian did all the machine work and balancing on this engine and I assembled it. The block was magged before any machine work was done and it checked out fine. Main clearances are .002 and the rods are .003, crank end play is .006 the rings are gapped at .026. You can smack it with some nitrous it is ready for it!