One of the many facets of building a hot rod at home is the creation of an exhaust system. Though header design and fab’ing might be best left to professionals (the meticulous work and time required to make a great set of headers may be cost-prohibitive to the home builder), the rest of the system can be assembled and finished by someone with decent welding skills, a basic selection of tools, and the right parts.
Gathering the right parts becomes easier with an introduction to Patriot Exhaust Products. One of the brands under the PerTronix Performance Products banner (the folks who make Ignitor electronic ignition parts and Flame-Thrower distributors), Patriot was brought into the PerTronix family in 2000, which expanded further with the acquisitions of Doug’s Headers in 2005, JBA Performance Exhaust in 2008, as well as the vintage Smithy’s Mufflers line.
Besides selling three types of mandrel-bent J- and U-bend tubing (1010 mild steel, aluminized, and stainless steel) to the homebuilder, Patriot also has gaskets, flanges, tips, mufflers, and more. For this project, a Patriot VaraFlow muffler was used, which features a small DC servo motor mounted to the side of the muffler that operates a butterfly inside. This not only changes the exhaust note (to the driver’s liking), but also gets rid of the droning exhaust noise that sometimes occurs at certain rpms.
Another way to help rid the exhaust system of an irritating drone is the addition of an X-pipe, which directs the exhaust in two different routes. The benefit of having the exhaust pulses interrupted by crossing over into another pipe before the muffler is an increase in low-rpm power. A custom X-pipe was fab’d for this ride using parts from Patriot, and it is something that a homebuilder could do himself, along with the rest of the exhaust system, so follow along and see how it was done. Read more
By John Baechtel
Extracting every last scrap of performance from a racing engine requires a detailed examination of each individual engine component to determine if there’s lost power due to undiscovered problems such as poor design, component compatibility issues or inaccurate tuning. Among the many critical components in your engine, the pushrod’s contribution is rarely considered as part of the overall power equation. For many builders, it’s simply a matter of selecting a hardened pushrod with the correct length and tip. Unfortunately that leaves a lot of untapped performance on the table, according to the experts at Manton Pushrods.
“The pushrod is the least considered part of any racing engine,” says Manton’s Al Perkins. “Pushrods are absolutely critical to valvetrain stability.” Read more
There’s one thing you can never have too much of in a racing engine, and that’s spark energy. Without the power to light your air/fuel mixture on fire, you’ll be going nowhere fast, and can in fact encounter many other issues as a result. Read more
EngineLabs: Self-tuning EFI systems are quite popular now, but is there a concern for breaking in a new engine with such a system?
Jones: Most important is that it not be overly rich during the break-in period. This is a very common issue with aftermarket EFI & carbs alike. It’s very important to get a proper air/fuel ratio as fast as possible. The newer systems do perform this fairly quick and are generally not a problem, but at the same time the end user needs to be sure it is correct. Overly rich fuel systems can “fuel wash” the cylinder, and the worst time for this is on a fresh engine. Read more