The still hypothetical Mazda RX-9is one of those cars that’s been anticipated for years, as it would be the latest in a long line of cars with a cult-like following: the Mazda rotaries. There hasn’t been a Mazda car since the back in 2012. The RX-9 was always assumed to be the heir to the big triangular rotary crown, but a rumor we heard today, from what we believe is a credible source, raises a lot of questions.

First, let me make absolutely clear this is nothing more than a rumor. Yes, the source claims they got it directly from a well-placed individual at Mazda. We’ve confirmed the source is related to Mazda in a way that could plausibly have put them in the sort of context they describe, but, to keep the source’s requested anonymity, that’s all I can reveal.

Here’s the rumor: Mazda is, in fact, developing an RX-9 sports car, and it should have a turbocharger and make between 350 and 450 horsepower. The big news is what it won’t have: a Wankel rotary engine.

Yes, in place of the expected rotary there will be six pistons, all in a row, an inline-six version of Mazda’s Skyactiv engine. for some time, and this has been confirmed by Mazda.

According to the March 2019 fiscal year results report, Mazda is apparently developing an all-new…

What’s surprising, of course, is the use of it in the RX-9. That’s not so much because it would be a bad choice—rotaries are very hard to make efficient, and it’s possible the time where rotaries actually were competitive and made sense has passed—but because the RX line of cars has always been about rotary engines.

Starting with the Mazda Cosmo, which we can think of as the RX-1, there’s been sporty Mazda rotaries called RX-2, RX-3, RX-4, RX-5, RX-7, and RX-8. Piston-engine sports cars Mazda has tended to name “MX” like the MX-6 or the Miata’s formal name, the MX-5.

Will the new RX-9 really end up being the MX-9? That doesn’t really feel right. But neither does calling a car an RX-something without a rotary.

Then again, maybe this is all just some filthy rumor?