Michigan Motorsports Stock Replacement 2.165"/1.590" LS Valve Set Fits 2007-Later Rectangle Port Head Casting Numbers 821 823 5364 Fits Engine Codes: L99 L76 L77 L92 LY6 L9H L94 L96 Includes 8 Intake Valves an 8 Exhaust Valves Michigan Motorsports' standard replacement valves are an affordable option to freshen up your stock or mild performance LS engine. These valves are designed to be a direct drop-in replacement for the factory Intake and Exhaust valves on the applications listed above. For higher performance and racing applications, be sure to check out our stainless valve options!