Could be the twin-turbo version of your 13B engine built to electricity the 3rd-generation RX-seven launched in late 1991. Just about every rotor on 13B-REW has an individual combustion chamber quantity of 654cc. With two rotors, the whole displacement was 1308cc. Perfect healthy for any Mazda swap or substitution task. https://waylongjlml.uzblog.net/details-fiction-and-mazda-13b-rew-motor-for-sale-52455783