Is the twin-turbo Model in the 13B engine created to energy the 3rd-era RX-7 introduced in late 1991. Each individual rotor on 13B-REW has a single combustion chamber volume of 654cc. With two rotors, the entire displacement was 1308cc. Fantastic in shape for just a Mazda swap or replacement job. https://www.nwjdmmotors.com