"It's a monster, in more ways than one," says Crew Chief Mike Kloeber, referring to the huge wing cantilevered over the rear of a top fuel dragster. The sole function of this behemoth is to generate thousands of pounds of downforce, keeping the vehicle's tires firmly planted on the track while it hurtles along at speeds of more than 300 mph. "The problem is that if we lose the wing (not uncommon when a tire blows), then Newton's Law takes over and the rest is history," he says. Looking to improve safety, Kloeber surmised that the addition of a sidepod would reduce the reliance on the wing, and potentially cut down on aerodynamic drag. (Common on Formula 1 and Indy cars, a sidepod causes the airflow under the vehicle to speed up, creating a low-pressure region that, in effect, sucks the vehicle to the ground.) By moving the center of pressure closer to the front of the car, Kloeber figured the sidepod would improve vehicle stability and absorb energy in a side-impact crash. First, though, he had to find a way to test his theory out—no small feat, given that IHRA teams don't typically have big budgets for research and analysis compared to other leagues. "There's a lot of seat-of-the-pants engineering going on," admits Kloeber. Fortunately, John Moloney with ARC, a division of Penske Racing, helped get Kloeber in touch with a U.K. company called Advantage CFD, which has done significant analysis work for other racing teams. Advantage evaluated several different sidepod geometries and other aerodynamic enhancements, including an exhaust shroud and gurney flap. Results confirmed Kloeber's hunch—that enough downforce could be created by a large sidepod wing to allow a redesign of the rear wing. Kloeber won't say exactly what changes he is making, but he plans to unveil a concept dragster in June. Next up: He will present his study results to the IHRA sanctioning bodies in the hopes of convincing them to change the design rules and make dragster racing safer at any speed. For details on Kloeber's CFD analysis, go to http://rbi.ims.ca/3849-532.
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