(12 pack) Pontiac Firebird/GTO/LeMans 326-455 V8 Stainless Steel Long Tube 4-1 Header Exhaust Manifold

The exhaust manifolds found on the 1964-1979 Pontiac small block 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 Long Tube off-road racing headers are designed to allow the exhaust gasses to flow more freely from each cylinder and combine in a more efficient manner. Tubing has been optimized for the 5.7L(350ci), 6.6L(400ci) and 7.5L(455ci) 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. Specification: Made of High Quality T-304 Stainless Steel with Computerized Mandrel-Bends for Strength and Durability i.e. Maximizing Smoothest High Exhaust Air Flow Rate TIG Welded CNC Machine Flange Offers the Best Flow Characteristics for the Engine at High Engine Speeds Increase High Flow Air, Instantly Gain 10 -15 Hp. / Tq. Inlet: 1 7/8" OD / Outlet: 3" OD / Collector Outlet: 2.5" OD / 16 Gauge Wall Piping / 10mm Thick Header Flange Package Included: 1 x Set of Exhaust Headers Fitment: 64-70 Pontiac Tempest 64-77 Pontiac LeMans 64-73 Pontiac GTO 67-79 Pontiac Firebird 70-74 Pontiac Grand Prix 73-75 Pontiac Grand Am 75-77 Pontiac Grand LeMans Fits Round Port Engines Only Does not fit D-Port Models

This item fits: 64-70 Pontiac Tempest / 64-77 Pontiac LeMans / 64-73 Pontiac GTO / 67-79 Pontiac Firebird / 70-74 Pontiac Grand Prix / 73-75 Pontiac Grand Am / 75-77 Pontiac Grand LeMans TIG Welded CNC Machine Flange Offers the Best Flow Characteristics for the Engine at High Engine Speeds