Manley Performance crankshafts are designed with the highest standards in mind. Each crankshaft is put through a multi-step heat treatment process and nitrided (hardened) for maximum strength. The crankshaft is then stress relieved, shot peened, and magnafluxed (stress tested). The center, crank pin and counterweights are gun drilled for reduced weight. Manley Turbo Tuff Billet 4340 Evo crankshafts are the perfect crank to complete a stout bottom end build if massive horsepower is your goal. Manley Turbo Tuff Series Billet Mitsubishi crankshafts feature uniquely designed, ultra-lightweight, full contoured counterweights resulting in reduced windage and maximum performance.