Could be the twin-turbo Edition from the 13B engine meant to electric power the third-technology RX-7 released in late 1991. Every single rotor on 13B-REW has one combustion chamber volume of 654cc. With two rotors, the full displacement was 1308cc. Best match for just a Mazda swap or substitute project. https://rotary-engine-rx788260.educationalimpactblog.com/60294598/rx7-motor-things-to-know-before-you-buy