For correct machine-in seal - see Part No. C13-9112
You will also need to purchase our 2 piece spacer set and extra long pulley bolt for press-in applications - see
Adding weight to the rotating engine assembly is nothing new. Many Chevy- Ford and other domestic engine builder have been doing this for years. Adding a Overweight pulley onto the end of your crank can help to absorb some of the engines harmonic vibrations. For racing and performance applications- the extra weight can help to reduce crankshaft twisting and aid in leaving the starting line by reducing engine bog. These pulleys are also very helpful for off-road and Sand Buggy engines when you want to start out in second gear. Super strong one piece construction and virtually unbreakable.