We have been having an email conversation with Jamie Joyce, who manages Automotive R & D for Doug Thorley headers. In our previous post we got some interesting background information on the differences between Doug Thorley headers and a stock Toyota Tundra exhaust manifold. This time, we’ll get a chance to hear some of Jamie’s answers regarding the thorny issue of short tube headers versus long tube headers in the pickup truck world.
We started out by mentioning to Jamie that both the short and long tube header options offered by Doug Thorley appeared to offer a similar increase in low-end torque, with only a slight advantage going to the long tube units. This seemed to go against the conventional wisdom in the truck performance world that short tube headers can actually rob an engine of low rpm torque, especially in comparison to stock manifold designs.
Jamie told us that historically,
Doug Thorley is a respected name in the headers business, having honed its reputation over 50 years as a brand that can be counted on for excellent quality, factory fit and durability. In addition to building after market headers for a wide range of vehicles – including the Toyota Tundra – Doug Thorley Headers has also served as an OEM manufacturer for Suzuki of America, Honda’s AMA superbike race team, Kawasaki of America and even TRD, amongst others.
We interviewed Jamie Joyce, the Automotive R & D Manager for Doug Thorley Headers, last week in order to ask some questions about general questions about headers, and specifically how they can help improve the Tundra’s performance.
Earlier this week we asked the question Should You Add Headers to your Tundra? The answer? It depends. While headers will definitely improve the performance of a bone-stock Tundra, they’re more beneficial on trucks that already have copious performance upgrades. After-market headers are performance multipliers – they’ll add at least 10 horsepower on a stock truck, but some people have gained 20 or even 30 horsepower on Tundras that have significant performance upgrades like a UniChip engine tuner or a supercharger.
Let’s take a look at three popular header choices for the Toyota Tundra and see how they stack up against each other.
Search terms people used to find this page:
- installing short headers on 2007 tundra
When it comes to adding power to your Tundra, replacing your stock exhaust manifolds with headers is an option worth exploring. Stock exhaust manifolds are typically designed with low cost in mind, and on many vehicles they are restrictive and inefficient when compared to after-market headers. On most vehicles, replacing the stock exhaust manifold with headers will remove flow restrictions inherent in the standard system and scavenge as much exhaust gas as possible out of the engine. For most trucks (especially trucks made more than 5 years ago), headers are a great way to add decent power to a stock engine.
However, fans of the 2nd-generation Tundra know that the stock exhaust manifold on the 4.6L and 5.7L Tundra is actually quite good. In fact, the stock exhaust manifold on newer Tundra trucks is one of the more sophisticated factory exhaust manifolds you’ll find. They’re an efficient stainless steel 4 into 2 into 1 design, a configuration that’s known for moving exhaust gases quickly. The Tundra’s stock exhaust manifold tubes are also equal length for each cylinder. Equal length tubes are important because they facilitate consistent back pressure in each cylinder, improving overall performance.
The bottom line for 2nd-gen Tundra owners (07′ and up models) is that replacing the standard exhaust manifold with a set of less restrictive after-market headers isn’t going to result in huge gains. Still, that’s not to say that adding headers to a Tundra will have no impact.