Every Gibson Performance Header is Dyno - tuned and engineered to deliver more usable horsepower and torque at low and mid - range RPM highway speeds. Improves engines ability to breathe and cooler operating engine temperature. Designed as a direct replacement for the factory manifolds, using the stock crossover pipe. They are well suited for lowered and raised vehicles, street and off - road. 50 State Street legal. Meets EPA and CARB requirements. Will not affect the factory warranty. No welding required. Uses OEM style connections. 38 in. Heavy Duty Laser Cut Port Flanges - No Warping or Leaking. Premium Gaskets and Hardware included. Backed by a Lifetime Limited Warranty.