These Men Put Together a Rotary Engine from the Ground Up

Joe from Mantella Autosport builds a Mazda Renesis 13B engine from the ground up.
Jessica Miley

This is a must see video for all engine nerds. Joe Ferguson from Mantella Autosport builds a Mazda Renesis 13B rotary engine from parts on the table to the final turn of the torque wrench. Joe is joined by his friend Dave as they explain in detail each step of the process as well as explaining how the engine is actually going to function. The two guys are super knowledgeable and are able to discuss the how the unique Wankel combustion process works in a way that is practical without being annoying. If you are a Mazda engine fan, you’ll also appreciate the discussions on the strengths and weaknesses of the Renesis vs older versions of the 13B.

Wankel engines are popular with car builders and racers because of their relatively compact size and ability to be tuned up. They have a high power-to-weight ratio but are also famous for poor fuel efficiency. The 13B that you’ll see in this video was the most widely produced engine being in production for over thirty years. Despite its name, the 13B engine is not related to the 13A engine. It is actually closer to the 12A engine, though with lengthened rotors. In the United States, the 13B was on the market from 1974 until 1978 and then made some appearances again in the 80’s and 90’s. The engine was available in Japan from 1972 up until the 2002 RX-7 model.