These pushrod sets are available in either Chromoly or lower-priced aluminumThe aluminum pushrods are lighter and quieter while the Chromoly pushrods are more rigid and provide more strength in high-performance applicationsAll of these pushrods are the same diameter as stockThese pushrod sets are available in either Chromoly or lower-priced aluminum The aluminum pushrods are lighter and quieter while the Chromoly pushrods are more rigid and provide more strength in high-performance applications All of these pushrods are the same diameter as stock