What does 13A stand for? 

13a

The Mazda Wankel engines are a family of Wankel rotary combustion car engines produced by Mazda.Wankel engines were invented in the early 1950s by Felix Wankel, a German engineer. Over the years, displacement has been increased and turbocharging has been added. Mazda rotary engines have a reputation for being relatively small and powerful at the expense of poor fuel efficiency. The engines became popular with kit car builders, hot rodders and in light aircraft because of their light weight, compact size, tuning potential and inherently high power-to-weight ratio—as is true for all Wankel-type engines. Mazda put the engine into series production with NSU (Ro80) and Citroën (GS Birotor) as part of the Comotor joint-venture between 1967 and 1977. Since the end of production of the Mazda RX-8 in 2012, the engine was produced only for single seater racing, with the one-make Star Mazda Championship being contested with a Wankel engine until 2017; the series' transition to using a Mazda-branded piston engine in 2018 completely ended the production of the engine, although Mazda have proposed several concepts for the engine's future.

see more »