Long Tube Headers with Adapters
1964-73 Pontiac GTO / Lemans
1967-74 Pontiac Firebird / Trans Am
1969-74 Pontiac Grand Prix
326-455 V8 (D-port only)
Part# THY-341-C

Application notes: 3-tube header (middle two ports combined) | Automatic transmission only | Some late model applications may require drilling and tapping of end holes in cylinder head | No steering column shift

Header Style: 3:1 Long-Tube Headers 
Material: Steel
Finish: Silver Ceramic Coated
Primary Tube Diameter: 1-3/4"
Primary Tube Gauge: 14 Gauge
Collector Attachment: 3 Bolt Flange
Collector Diameter: 3"
Tuned: No
Flange Thickness: 3/8"
Bolts and/or Studs Included: Yes
Gaskets Included: Yes
Reducers/Adapters Included: Yes
Y-Pipe (Crossover) Included: No
Weld Up: Adapters must be welded to exhaust system
Quantity: Sold as a Pair
CARB E.O. #: N/A
Warranty: Limited Lifetime to original purchaser

Backed by over 50 years of knowledge and experience, our headers are designed to outflow your stock exhaust manifolds by leaps and bounds. These headers will give your engine more horsepower and torque across the entire RPM range, no doubt about it! To make these headers last, we made them out of industry leading 14-gauge mild steel tubing with 3/8" thick flanges. Topping all of that off, all of our headers come beautifully ceramic coated to greatly reduce under-hood temperatures and protect the headers from the environment. All of this 100% American made, and backed by our lifetime warranty of course!

Unless otherwise noted, these headers are designed to fit the vehicle as it came from the manufacturer. This includes components like cylinder heads, chassis, steering, motor mounts, body mounts and bushings, etc. If your vehicle is using aftermarket components, parts from other applications, or custom altered parts, then it is the installer's responsibility to verify fitment.