Billet Hardened 4340 Chromoly Crankshaft . Features a true 1/8" journal radius for strength and durability. Also features airplane wing style counter weights that are proportionally designed for superior balance. The #6595-C crankshaft was designed for aftermarket flathead blocks that have extra spacing between the crank and cam. Will not fit the Briggs Raptor and Blockzilla blocks and requires large gear set for the aftermarket flat head blocks. 3.00"(+.563) stroke with a .998" rod journal.