It carries the most notable audio note of all time, one that sounds more Formula 1 than … well, modern Formula 1 engines, and one that, for many, is the ultimate-sounding motor, even if you’re not a fan of rotaries. We’re talking, of course, about the myth, the legend, the holy grail of all Mazda power plants: the Mazda four-rotor, aka ‘quadrotor’, aka ‘26B’, aka ‘13J’—never offered for sale to the public, never released as a production engine in any Mazda, and only ever used in a handful of race cars, including the ’91 Le Mans–winning Group C car. All this only helps to make these engines the holy grail of swaps to many — a swap that is only made possible by some very clever Kiwis who produced their…