The exhaust manifolds found in the 1967-1987 Chevrolet Pontiac Buick and Oldsmobile engines 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 Style 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 Small Block 265/267/283/302/305/307/327/350/400 cubic inch 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.

This product is compatible with:

Chevy 265-400 Cu.In. Small Block GEN I V8

• Precision machined steel flanges that provide a tight seal at the head and allows a high flow rate through the primary tubes
• Made From High Quality T304 Stainless Steel For Strength & Durability
• Constructed With TIG Welded CNC Machine Flange For Percision & Fitment
• All Tubing Is Mandrel-Bent
• Comes With Metal Gasket

Precision machined steel flanges that provide a tight seal at the head and allows a high flow rate through the primary tubesAuto Dynasty