Would be the twin-turbo Variation with the 13B engine made to electrical power the 3rd-era RX-7 introduced in late 1991. Every single rotor on 13B-REW has an individual combustion chamber quantity of 654cc. With two rotors, the whole displacement was 1308cc. Great match for the Mazda swap or replacement undertaking. https://andersonirsqv.blogkoo.com/mazda-13b-motor-for-sale-an-overview-49405029