May be the twin-turbo version with the 13B engine meant to ability the third-era RX-7 introduced in late 1991. Each individual rotor on 13B-REW has just one combustion chamber quantity of 654cc. With two rotors, the whole displacement was 1308cc. Best suit for just a Mazda swap or substitution project. https://13b-turbo-for-sale01234.azzablog.com/39285503/the-smart-trick-of-mazda-rx-7-engine-that-no-one-is-discussing