The tire was one of the things I wanted to see on the video if there is one. I run a 16X32 tire but I run almost 10 psi of air in them in a car that's about 50-70 lbs. heavier. I found in my own car that the 60 ft. was almost all suspension and pitch rotation. The times show the power is there. If the tire is wadding up it will kill some of the 60 ft. But I think there will be a combination of things and a picture is worth a thousand questions. A video would help a lot. I used to launch at 4800 with GY slicks but since I went to MTs and got the tire pressure right I can launch at 4600 and still get good 60s. I run a 4.86 rear gear as I only run 1/8th mile. The 4.30 gear will also make a difference. If the car isn't pitch rotating then the front will need to be loosened up and/or a 4link change would need to be made. A lot of unanswered questions yet.
George