SCORE Journal - The Official Publication of SCORE Off-Road Racing
Issue link: https://read.uberflip.com/i/680178
determine what works best for any given application, or terrain. Obviously, if you don't have an engine builder or if you're running a stock class, then any of the leading aftermarket exhaust system The question remains. How do racing exhausts differ from ordinary street exhaust systems? To thoroughly answer that question, SCORE Journal interviewed some of the leading suppliers and builders of desert racing vehicles and associated exhaust systems — from Trophy Trucks to UTV classes, in hopes of further understanding their challenges and goals when it comes to exhaust systems for the desert race environment. The Exhaust Industry "A racing exhaust system can help tune the engine's torque or power curve. While working with the correct selection of engine bore/stroke, cylinder head, camshaft and intake system, the exhaust system becomes a tool to help dictate the where in the RPM range you can make power and torque," says Kevin Kroyer of Kroyer Racing Engines in Las Vegas, Nevada. Kroyer was named SCORE Trophy Truck Championship Engine Builder of the Year and NASCAR Clevite Engine Builder of the Year several years running. His racing engines have won a string of championships in both NASCAR and SCORE races. "We don't use any out of the box exhaust systems. We usually are working in the Trophy Truck class and they have special size and fitment issues, so out of the box doesn't usually fit the package," said Kroyer. "Mufflers are sometimes EXHAUST SYSTEMS SAY A LOT ABOUT A VEHICLE, AS WELL AS ADD TO ITS PERFORMANCE. THE BEAUTY COMES FROM HOW IT'S DESIGNED AND FLOWS WITHIN A WELL-BUILT CHASSIS. EXHAUST SYSTEM SCIENCE manufacturers can guide you in determining what off-the- shelf system works best. A Brief Overview Let's start by understanding the objective of a racing exhaust system. Its first job is to release swirling spent gases produced by engine combustion through a collection of piping we call the exhaust system. The configuration, length, metallurgy, and diameter of the piping which extends from the engine's exhaust manifold back through the tailpipe, affects the velocity, temperature, and turbulence of the air being released. Ideally, a good exhaust system will take all of these things and more into consideration to produce optimum air-flow with the least amount of restriction and noise. While many might think that noise shouldn't be a factor in racing, the facts are that an overly loud exhaust system becomes a distraction to the driver and co-driver, keeping them from communicating properly and drowning out other vehicle noises that can be an indication of a problem. 067 SCORE JOURNAL COURTESY THE ROADSTER SHOP