The Edelbrock Timing Chain Set is a true Roller timing chain set, utilizing a solid-bushing chain that rolls with the sprocket on a true bearing surface, eliminating chain stretch. They can be used with Edelbrock or stock camshafts and have cam sprockets made from 35, 000 psi tensile strength cast iron and billet steel crank sprockets that have been induction heat treated. Most sets have three keyways to ensure accurate timing for early or late-model vehicles, and to allow you to set cam timing 4 degrees advanced, 4 degrees retarded, or stock. However, 50-state legal (stock replacement) sets have single keyways. Performer Link timing sets are not for use above 6500 rpm.