13b FD3S Rotary Miata Dyno backfire

13b FD3S Rotary Miata Dyno backfire

13b fd3s engine with PT 6265 bb turbo. Msds. 4"intake. 3" full exhaust. Power fc ecu. 8.8 ford rear with 3.23. Dynoed at 324 whp. 10psi