Except for a difference in pitch size, the same Poly Chain GT2 belt that powers dragsters at speeds exceeding 330 mph is widely found on HVAC units, conveyors, and food and beverage-handling drives.
Manufactured by Denver-based Gates Corp., the toothed belt drives the supercharger (blower) on engines that produce an estimated 8,000 hp an application that pushes belt technology to the extremes, says Brent Oman, Gates motorsports belt engineer. Punching the throttle accelerates the engine crankshaft from idle to more than 9,000 rpm. When the driver eases up, the engine slows to as little as 2,000 rpm. But while rpm quickly drops, the blower's inertial load wants to maintain speed. Sudden acceleration and deceleration instantly changes tension and speed and can quickly destroy a belt, explains Oman.
The Poly Chain GT2's polyurethane construction handles such loads well, says Oman. GT2 users include Top Fuel and Funny Car teams such as Tony Schumacher, the 2004 Top Fuel world champion and current points leader. Schumacher's crew chief Allen Johnson says mechanics prefer not to make tuning changes to the dragster between rounds, and the GT2 is one component that needs no attention. "During our championship season, we didn't have a single belt failure," he says.
Originally designed to replace roller chain on industrial drives, Poly Chain GT2 belt is typically used on high-torque synchronous drives up to 1,000 hp. Gates officials say it is lighter and needs less space than roller chain and rubber synchronous-belt systems. And it saves on maintenance, as the clean-running systems need no expensive oil baths or lubrication.