- Billet Aluminum Main Caps for Coyote Will work on Gen 1/2/3 and GT350/Predator Blocks Uses standard Coyote Main Bearings and Hardware Will require Line Bore for fitment Made from 6061 Material We have made 2500+whp with this Main Caps on a Production Tkm Prepped Block and Stock Crank Machined in house at TKM Performance