The exhaust manifolds found in the 1988-1997 Chevrolet / GMC Pickups and SUVs were designed to combine the exhaust gasses from each of the cylinders quickly with a manifold that was cost effective to produce. Our long tube 4-1 off-road headers are designed to allow the exhaust gasses to flow more freely from each 4 cylinder bank and combine in a more efficient manner. Tubing has been optimized for the 5.0L(305ci) and 5.7L(350ci) engines. This creates a reduction in cylinder backpressure and improved exhaust gas velocity. These improvements free up lost horsepower and torque. An added benefit is a more performance oriented exhaust sound.
Pair of 4-1 Design / 3-Bolt Flange / Bolts to OEM Y-Pipe 1.5" ID Inlet / 2.125" ID Outlet / O2 Sensor Bung Included on Driver Side TIG Welded CNC Machine Flange Increase High Flow Air, Instantly Gain 10 -15 Hp. / Tq.This product is compatible with: 88-97 Chevy/ GMC Pickups/ SUVs without Air Injection (5.0L & 5.7L Only)