Though rotaries haven’t made much of a mark in big-name racing in a few years, their compact construction and smooth power delivery keep them popping up in different mid-level categories. It’s not surprising then, that with a huge Mazda community in Australia, a set of former Grand-Am RX-8s made their way into the Bathurst 12 Hours two years ago.
Bruce Henley continues to race these pristine 3-rotor monsters, which, while appearing to share the same frame with a road-going Mazda RX-8, are far from the production car in just about every way. These machines utilize a space frame, and do not use the standard 1.3-liter 13B Renesis engine we all know and love. Instead, a peripheral-port 20B sits flush against the firewall.
The 2.0-liter motor is a joy to listen to. Screaming and wailing in a way only a rotary can, they spit flames and pop wildly as the driver hops off the throttle to change gears. At low revs, the gurgle of the 20B is unmistakable, and their butter-smooth power delivery makes them particularly effective.
The Mazdaspeed-built mills chuck out somewhere in the range of 400 WHP, which put them in contention with the Porsches and Pontiacs running alongside in the Grand-Am races from 2007-2012.
Running extremely rich and using an additional injector to spray the exhaust, plenty of fuel was burned to keep these motors cool throughout their two-hour Grand-Am races. For the 12 Hours at Bathurst, one can only imagine the stresses they underwent.
In their heyday, the Grand-Am spec RX-8s managed 18 class wins; however, the finicky rotary left some teams scratching their heads. It’s a relief to see that there are still those who are willing to put up with the fragility and keep these rotaries running in competition.