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Doug's Headers D521-B Full Length Header 1-3/4 In, 65-68 Catalina, Blk

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#447D521B

Doug's Headers D521-B Full Length Header 1-3/4 In, 65-68 Catalina, Blk

Name: Doug's Headers D521-B Full Length Header 1-3/4 In, 65-68 Catalina, Blk
Brand: Doug's Headers
SKU: 447D521B
Price: 1023.41 USD
Availability: InStock
Rating: 5 (1 reviews)

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Specifically designed to fit the 65-68 Catalina platform
Manufactured with CNC mandrel bent tubes for an accurate fit & better flow
The precision formed long transition collectors and long tube design will reduce backpressure and increase horsepower

$1,023.41

/set

Factory Shipped

$1,125.75

Save $102.34

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Product Summary

Long Tube Header Tube Type, D-port Exhaust Port Shape

Specifically designed to fit the 65-68 Catalina platform
Manufactured with CNC mandrel bent tubes for an accurate fit & better flow
The precision formed long transition collectors and long tube design will reduce backpressure and increase horsepower
Has 3/8" Thick machined flanges that will not warp
Tubes are pre-polished to remove scratches and the header is finished with a Hi-Temp Black Coating

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Key Specs

MFG. Part #	D521-B
Header Tube Type	Long Tube
Exhaust Port Shape	D-port
Flange Style	Standard
Primary Tube Diameter	1-3/4"

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Need To Know

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855.313.9176

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Doug's Headers D521-B Details

Doug's PASSENGER CAR HEADERS Long Tube Hi-Temp Black Coated Header 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 machined 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 Hi-Temp Black Coating

Doug's Headers D521-B 1 3/4" 4-Tube Full Length Header Pontiac Catalina 326-455 65-68 Hi-Temp Black Coating
Black
Collector: 3
Port: D
Primary: 1 3/4
exc. states w/Calif. emission stds
removal or modification of locking steering column reqd
factory heads w/o end bolt holes must be drilled and tapped
with Floor Shifter
with A/C
For Off-Road Use Only

Doug's Headers D521-B 1 3/4" 4-Tube Full Length Header Pontiac Catalina 326-455 65-68 Hi-Temp Black Coating
Black
Collector: 3
Port: D
Primary: 1 3/4
exc. states w/Calif. emission stds
removal or modification of locking steering column reqd
factory heads w/o end bolt holes must be drilled and tapped
with Floor Shifter
with A/C
For Off-Road Use Only

Application

1965-1966 Pontiac Bonneville 6.4L/389 V8
1967-1968 Pontiac Bonneville 6.6L/400 V8
1965-1966 Pontiac Bonneville 6.9L/421 V8
1967-1968 Pontiac Bonneville 7L/428 V8
1965-1966 Pontiac Catalina 6.4L/389 V8
1967-1968 Pontiac Catalina 6.6L/400 V8
1965-1966 Pontiac Catalina 6.9L/421 V8
1967-1968 Pontiac Catalina 7L/428 V8
1965-1966 Pontiac Grand Prix 6.4L/389 V8
1967-1968 Pontiac Grand Prix 6.6L/400 V8
1965-1966 Pontiac Grand Prix 6.9L/421 V8
1967-1968 Pontiac Grand Prix 7L/428 V8

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Aeromotive & PerTronix Black Friday 10% Off Sale

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Guides & Documents

Choosing the Right Headers

Headers Installation Instructions (447D521B)

CARB Warning

For use on pre-1966 vehicles only

Emissions warning: this part only legal for sale or use in California if installed in vehicles model-year 1965 or older; motorcycles model-year 1977 or older; or off-highway recreational vehicles (such as off-road motorcycles and all-terrain vehicles) model-year 1996 and older. ++any other use renders the vehicle tampered and not legal for use on California public highways (any public street or roadway, public dirt road, public park, or publicly maintained right of way open to the use of the public for vehicular travel). Violations subject to $37,500 penalty per violation per vehicle, revocation of registration, loss of use on California public right of ways, and proof of correction for tampering there are similar restrictions and penalties under federal law and the laws of all other states with penalties under federal law of up to approximately $45,268 per tampered vehicle and/or engine.

CA WARNING:

Can expose you to lead, a carcinogen and reproductive toxicant. See www.P65Warnings.ca.gov

CARB warning

Doug's Headers D521-B Specifications

KEY SPECS
MFG. Part #	D521-B
Brand	Doug's Headers
Header Tube Type	Long Tube
Exhaust Port Shape	D-port
Flange Style	Standard
Primary Tube Diameter	1-3/4"
Material Type	Steel
Color	Black
Weld-Up	No
Collector Diameter	3 Inch
Finish	Hi-Temp Black
Hardware Included	Yes
Gasket(s) Included	Yes

GENERAL
Sold in Quantity	Pair
GTIN Code	694342543587

Ratings & Reviews

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Great product

5.0

4 months ago

Lake Havasu

Verified

Fitment great

Would Recommend

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Questions & Answers

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Fitment

1959-1966 Pontiac Bonneville

389 Pontiac V8

1959-1966 Pontiac Catalina

389 Pontiac V8

1962-1966 Pontiac Grand Prix

389 Pontiac V8

1964-1966 Pontiac GTO

389 Pontiac V8

1963-1966 Pontiac LeMans

389 Pontiac V8

1959-1966 Pontiac Star Chief

389 Pontiac V8

1961-1966 Pontiac Tempest

389 Pontiac V8

1960-1961 Pontiac Ventura

389 Pontiac V8