The 1979 Mazda RX-7 was a milestone sports car. It was nimble, affordable, and thanks to its unique rotary engine, very quick. But over 16 years and three generations, the RX-7 grew rapidly in performance and price, until its demise in 1995. Still Mazda promised the rotary RX would return, and with the 2004 RX-8, that pledge finally has come true. But with a rear seat, and four doors, is the new RX-8 sports car, a sport sedan, or just a good sport?

Let’s get the trivial stuff out of the way first. If you think having rear seats disqualifies the 2004 Mazda RX8 as a sports car, then you can count out the Porsche 911, too. And while the four doors are special, we’re not sure small, rear opening access panels qualify as true doors.

Moreover, the RX-8 has what makes a modern sports car in the first place. A finely tuned, rear-wheel drive chassis and lightweight multi-link suspension that puts handling at the top of its to-do list. Easy power through a drive-by-wire throttle that under an educated foot can be played like a fine instrument. Plus, four-wheel vented disc brakes with ABS, that only know how to...