While the Wankel rotary engine does indeed make a lot of power in a small, lightweight package, it does so while burning lots of fuel and emitting lots of noxious gases into the atmosphere, at least when running on gasoline. And that means the rotary engine will likely only ever be able to power niche vehicles. And that, in turn, means that it is very difficult to turn a profit on vehicles with rotary engines, particularly for a small automaker like Mazda.
"It has to be a viable commercial proposition. If we are going to adopt it, it has to be a product that can generate at least sales of 100,000 units a year. We have to be able to achieve a profit," said Kogai in an interview with Automotive News. Mazda sold 56,203 RX-7 models in the United States (the automaker's biggest market) in 1986. Sales of the RX-8 peaked in 2004, its first full year on the market, with just 23,690 units.
There is a sliver of hope, though. "We are the first and only manufacturer to commercialize the rotary engine. In that respect, we have some responsibility," said Kogai. Research will continue on the rotary engine at Mazda, and, since the engine will run on a wide variety of fuels, including hydrogen, it is possible that we'll see a rotary return on an alternate fuel sometime in the not-too-near future.