ProMax Ford 351C 4.000 4340 Alloy Crankshaft American Made! Starting with the finest high purity 4340 aircraft quality high nickel alloy. Many manufacturers state they use 4340, but very few use the same quality. There is a difference! These forgings have high quantities of nickel and chromium, which insures strength and long service life.

These forgings are shipped to the leader in high performance crankshaft machining, Callies Performance Products. They are machined to the highest specifications, with roundness within 60 millionths and taper being held to within .0003” on all rod and main dimensions. All journals have .125” Tru-Form radii. 1” Angalite lightening holes in all rod throws. Callies ”Deep Case” hardening produces a wear layer that remains intact even if reground .010” under (other cranks have a hardness depth as little as .003”). Journals are micro-finished to 5 microns or better. The best forgings, the best machining, and best hardening. Which crank will you run? Requires chamfered bearings.