RC fuel injectors US made: suggested flow 550 cc for power up to 100 hp per cylinder, 750 cc. for power up to 150 hp per cylinder (600 hp on a 4 cylinder engine): the suggested power ranges are based on our experience for best results, however it is possible within reasonable limits goin further in the power output playing with fuel pressure or close to the duty cycle limit, but this can only be done when you strictly monitor individual cylinder egt.