May be the twin-turbo version with the 13B engine designed to power the 3rd-technology RX-7 launched in late 1991. Each rotor on 13B-REW has an individual combustion chamber quantity of 654cc. With two rotors, the overall displacement was 1308cc. Perfect in good shape for any Mazda swap or substitution project. https://rx7engine03568.blogdal.com/39400405/the-mazda-rotary-engine-sale-diaries