Doug Thorley Headers

Doug Thorley Headers Cat-back Exhaust, Axle-back Exhaust, Headers, Mid-Pipes and Exhaust Products

For over 60 years, Doug Thorley Headers has been an innovator in the automotive aftermarket. Driven by a passion for performance headers and superior quality exhaust systems, Doug Thorley Headers is committed to developing 100% American-made products that will reliably deliver maximum horsepower and torque. Doug Thorley Headers has been pushing the limits of automotive technology since first inventing the Tri-Y Header in 1958, and they do it all on American soil.

Every vehicle model is unique, and the Doug Thorley R&D team is constantly working to provide a diverse range of products and applications to meet demand. Whether you are hauling an RV, building up a street hot rod, or just looking to get a little more punch out of your Smart Car, Doug Thorley Headers has the best performance headers to maximize horsepower and torque for your application.

Why the Tri-Y? Serious Horsepower, that’s why! Invented by Doug Thorley Headers, the Tri-Y header is designed to match the synchronization of the engine firing order, thereby maximizing exhaust scavenging. This design creates the optimum torque and greatest horsepower gains in comparison to any other design.

Doug Thorley Headers operates under the principles of meticulous attention to detail and unmatched craftsmanship while their experienced staff continues to lead the way in automotive performance. Accesspeed is proud to offer Doug Thorley Headers products to our customers. With our low price match guarantee, you will always find the best combination of price and selection at Accesspeed.

Below are some of the Doug Thorley products offered by Accesspeed:

Short Tube Headers

Mid-Length Headers

Long Tube Headers

Sandrail Headers

50-State Legal Headers

Cat-back Exhaust

Axle-back Exhaust

Mid-Pipes

Exhaust, Mufflers, Headers and Tips » Long-Tube Headers

Long-Tube Headers

Do long tube headers increase horsepower?

Yes, long tube headers increase horsepower. If your state allows long tubes, this is a great investment in reliable performance.

Do long tube headers improve gas mileage?

Yes, from a technical standpoint. In most cases, fuel mileage will increase when you add long tube headers. The problem that Accesspeed customers have is keeping their foot out of the throttle because headers add so much horsepower.

Are long tube headers legal in my state?

If your state requires the OEM catalytic converters to remain stock, and in their original location, long tube headers are most likely illegal in your state, as these headers require modification or removal of the OEM cats.