I put a 2004R in my Barracuda and it made a big difference. I'm running 3.90 gears and the best part of all is that the noise level at 65/70 MPH has greatly decreased. Actually I can't hear the exhaust at all. 2300 RPM on the highway should let the motor last a lot longer as well. Oh yea...the gas mileage is great and the car is quicker off the line!!