4.250 stroke crank with 2.200 BB Chevy rod journal sizes, 7.100 long BB Chevy H beam forged steel rod, shelf piston with either a reverse dome or a dish that will give you between 10.0 to 1 to 10.7 to1 compression ratio with the aluminum heads you buy or lower the compression ratio to no more than 9.5 to 1 with your iron heads True roller timing set and degee the cam you select Six paks rock My last 400 block 518 C.I. stroker six pak motor made 720 HP with 712 Ft lbs on Oregon 91 octane pump swill That baby put many smiles on my face as well as made the old phincter pucker more than once on the street