1955-57 Chevrolet 396ci - 502Ci Big Block Doug'S Headers

Every header is tuned with the proper tube size and length to efficiently remove all the exhaust from each cylinder, reducing pumping losses for dramatic gains in horsepower and torque. Doug's headers are carefully developed on the vehicles they are i ntended to fit and are checked and rechecked numerous times during the design and manufacturing process. Once you check the heavy-duty 1/2" to 5/8" thick machined and finished header flanges, the smooth mandrel bent tubes, and the attention paid to assemb ly, you'll want Doug's.

The Metallic Ceramic Thermal Barrier Coating (MCTBC) is simply the best header finish on the market and is the standard finish on all Doug's headers. MCTBC protects and extends the life of headers by creating a thermalb arrier that significantly lowers under hood temperatures while protecting substrate metal from thermal fatigue.

Doug's finishes their headers with a vibratory finishing process that compresses and activates the coating, significantly increasing surface hardness to produce a coating 60% more corrosion resistant than standard header coating. This coating is easy to maintain and will not change color under normal operating conditions.

Doug's has made that commitment and their name has b ecome synonymous with quality. There's no compromise at Doug's.

Each header set includes all the necessary mounting hardware, collector reducers or connector pipes, premium gaskets and detailed installation instruction sheets. Our extra thick ga skets are rated up to 1100°F and are designed for an exact port match with Doug's headers.

Important: Be sure to read the important Application and Emission Notes listed below pertaining to each header system for correct application.

Note: Check your local or state laws before installing. Shipped oversize.

• With Air Conditioning
• With Power Steering
• With Power Brakes
• Automatic Transmission with Column or Floor Shift

• 2" tube diameter with 3-1/2" collector diameter and same as head ports
• Will not fit with manual transmission
• Will not fit if engine is more than 3/4" forward for HEI firewall clearance
• O riginal bellhousing frame mounts must be removed
• Will fit with 605 power steering box
• Does not fit 4 speed applications with bell housing mounts
• Header is designed to fit cars using original V8 pitman arm not 6 cylinder pitma n arm. Aftermarket pitman arms must be same as OE for proper header fit.

• This product is legal only for off-highway use (except in California or states that have adopt ed California emission standards), racing use or for use on pre-emission-controlled motor vehicles/motor vehicle engines (pre-1974 domestic vehicles certified to California standards, pre-1974 domestic vehicles certified to federal standards and all pre- 1974 foreign vehicles), per the manufacturer's application guide.