I currently have 4:57 gears in my car and they worked fine with my old motor. With my new motor I think I should go with 4:11's according to calculations. What do you think and what info do you need? The motor is a 351c-4v quench heads with a solid .554/.570 cam 238/248 duration. The cam card says 3000-6500rpm for best performance. C6 with 3500 stall and a 26" 10 x15 slick. Keep in mind I want the motor to last for a while thats why I figure 4:11's.