The exhaust manifolds found in the 1978-1991 Buick Chevy Oldsmobile and Pontiac Small Block engine were designed to combine the exhaust gasses from each of the cylinders quickly with a manifold that was cost effective to produce. Our 4-1 Mid-Length 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 5.7(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.
Made of High Quality T304 Stainless Steel Material
Inlet Outlet: 1.50" 2.50"
O2 Sensor Bung Insertion and Metal Gasket Included
TIG Welded CNC Machine Flange
Increase High Flow Air, Instantly Gain 10 -15 Hp. Tq.
No instructions included
Professional installation is highly recommended
1 X Set of Header Exhaust System
Gasket(s) and Bolt(s) as shown if Any is Shown in the Picture Above
305-350 CID Engine Small Block
Please Check Compatibility