Yeah, we have a 69 340 4sp dart with 3.91 gears and it isn't fun on the highway. (Manageable, but not optimal) My dad has a 68 Coronet R/T that had the trac pac 4.10s in it. We built a 493 RB for the car and I went with 3:73 gears to try to be in the middle. What we found was that the motor had plenty of torque and we ended up switching to 3:23s for his car as well. Car actually feels faster and is much better on the highway. Decided to go the same route here.
