is the twin-turbo Variation from the 13B engine meant to ability the 3rd-era RX-seven released in late 1991. Every single rotor on 13B-REW has one combustion chamber quantity of 654cc. With two rotors, the full displacement was 1308cc. Ideal suit for a Mazda swap or substitution job.Drew Blankenship Drew Blankenship is a previous Porsche technician