- Standard size

- One-Piece Forging: Stronger and more reliable than two-piece valves

especially during the first few miles after installation

More on cylinder head sealing here

but Mishimoto saw some room to improve

BMW E9X M3 S65 Complete Exhaust System Dimensions:1.75" x 3" - Standard sizeBMW E9X M3 S65 Full Exhaust System Stainless Steel Performance Upgrade Maximize the power and sound of your BMW E9X M3 with a high performance full exhaust system, engineered for the 4. 0L S65 V8. This system is designed to optimize exhaust flow, delivering significant horsepower and torque gains while producing a deep, aggressive exhaust note without high pitched rasp. Available with 1 5 8" or 1 3 4" primary tubes, it provides an ideal balance of