May be the twin-turbo version with the 13B engine created to energy the 3rd-era RX-7 introduced in late 1991. Every rotor on 13B-REW has only one combustion chamber volume of 654cc. With two rotors, the full displacement was 1308cc. Best match for your Mazda swap or substitute challenge. I procured https://elliottqmlii.actoblog.com/39696046/what-does-13b-turbo-for-sale-mean