7.500 6.500 5/16 Pushrod Length Checker Easy and economical tool to layout and determine proper pushrod length for proper valvetrain geometry. Proper valvetrain geometry is necessary to obtain the desired results from the cam and to ensure damage is not done to the rest of the valvetrain. Made from a 5/16” pushrod that is cut and threaded with over one inch of travel. 5/16” ball tip on both ends.