Long Tube Headers for 64-67 GTO 326-455 1-3/4in Primary Black Coated D564-B

Overview:64-67 GTO 326-455 Long Tube Black Ctd Long tube headers provide the greatest increases in horsepower and torque across the entire RPM spectrum. The choice of racers worldwide, Doug's long tube headers are designed for the car owner who wants maximum power and the highest quality header on the market.Features: 3/8" Thick machined flanges to prevent warping Precision formed long transition collectors and long tube design reduces backpressure and increases higher RPM horsepower Heavy duty 16-gauge tubing for long life Tubes are pre-polished to removed scratches before applying metallic ceramic or hi-temp black coating Specs: Brand: Doug's Headers Collector Attachment: 3-Bolt Flange Collector Diameter: 3.0 IN Collector Port Diameter: 3.0 IN Color: Black Cylinder Head Port Shape: D-port Design: Full-length EGT Port: No Finish: Hi-Temp Black Coating Flange Thickness: 0.375 IN Gasket Or Seal Included: Yes Gaskets Included: Yes Grade Type: Performance Header Material: Steel Header Style: Full-length Material: Steel Mounting Hardware Included: Yes Oxygen Sensor Port: No Port Shape: D-port Primary Tube Outside Diameter: 1.75 IN Primary Tubing Diameter: 1.75 IN Prop 65 (C, R or CR): CR Prop 65 Yes/No: Yes Sheen Level: Matte Title: Doug's Long Tube Header 64-67 GTO 326-455 1 3/4" Primary 3" Collector Black Hi Temp Coated D564-B Tube Wall Thickness: 16 GU Part Number: D564-B Applications: 1964-1966 Pontiac GTO 389 CID 1967-1967 Pontiac GTO 400 CID 1964-1967 Pontiac LeMans 326 CID 1964-1967 Pontiac Tempest 326 CID Emissions:This product is Legal for use on Pre-Pollution Controlled Vehicles. It is legal for use on all vehicles produced Before Emissions Control Regulations were imposed. These are considered Uncontrolled Vehicles and are defined as follows 1965 and Older US Manufactured California Certified Vehicles 1967 and Older US Manufactured Federally Certified Vehicles 1967 and Older Foreign Manufactured Vehicles Instructions:Click here for installation instructions!Fitment Notes: Fits D-Port heads Only. Requires removal or modification of locking steering columns if equipped. Some factory heads do not have end bolt holes and should be drilled and tapped to assure proper sealing. Application with scatter shield or factory bell housings with dual starter pockets must use WIX oil filter PN 51522 or equivalent.