I made the switch from 4.10s to 4.30s in my Dart and I saw no difference but that was with my stroker motor with 502 lbs of torque because the 4.88s I had were too much with the rpms to high at the stripe. I now have my " small " 367 c.i. motor in and still run the 4.30s it could really use more gear I have 4.88s but the car is running and leaving good so the 4.30s might just stay in. A lot has to do with if the tracks around here switch to 1/8 mile from 1/4 as a lot of tracks are then the 4.88s would really be beneficial.