Doug's Headers D3373 Replacement Header, 1-5/8 In, 02-07 Chevy Truck

Doug's 2/4 WD TRUCK HEADERS Long Tube Metallic Ceramic CoatedHeader development and design is complex and requires a substantial amount of time and resources to do the job right! Many manufacturers are unwilling to make the commitment and instead offer compromised headers at lower prices. Doug's will not compromise performance, quality or fit to compete with inferior designs at cheap prices. Every Doug's header is tuned with the proper tube size and length to efficiently remove all the exhaust from each cylinder, reducing pumping losses resulting in a dramatic increases in horsepower and torque. Doug's headers are carefully developed on the vehicles they are intended to fit and are re-checked numerous times during the design and manufacturing process.

• 3/8" thick flanges... no warping
• CNC mandrel bent tubes... accurate fit & better flow
• Precision formed long transition collectors and long tube design... reduces backpressure and increases higher RPM horsepower
• Heavy 16 gauge tubing... longer life
• Tubes are pre-polished to remove scratches and the header isfinished with a Metallic Ceramic Thermal Barrier Coating polished to a high luster appearance offering corrosion and heat resistance up to 1400 degrees

• Doug's Headers D3373 1 5/8" 4-Tube Manifold Replacement Header Chevrolet Truck 5.3L 02-07 Metallic Ceramic Coating
• Shorty Design - Ceramic Coated
• Collector: 2 1/2
• Port Shape: SAP
• Primary Tube: 1 5/8
• 50-State Smog Legal header
• emissions code: legal only for off-highway use (except in California or states that have adopted California emission standards)
• with A/C
• CARB Executive Order D-57-19
• with Column Shift
• with Floor Shifter

• Doug's Headers D3373 1 5/8" 4-Tube Manifold Replacement Header Chevrolet Truck 5.3L 02-07 Metallic Ceramic Coating
• Shorty Design - Ceramic Coated
• Collector: 2 1/2
• Port Shape: SAP
• Primary Tube: 1 5/8
• 50-State Smog Legal header
• emissions code: legal only for off-highway use (except in California or states that have adopted California emission standards)
• with A/C
• CARB Executive Order D-57-19
• with Column Shift
• with Floor Shifter

Installation Instructions (PDF)