Are you still leaving at idle? Have you tried loading the converter and just rolling into it. If you are spinning at the hit this could help. this seems counterintuitive but I run half the rear tire and if I don’t load the converter it flashes too high and snaps the tire loose at the hit. The stall rpm is different than the flash rpm. I load it enough that the car launches but doesn’t blow the tire off. I have a 9.5” ptc converter that flashes to about 3500 my best 60’ is 1.71 have someone with an iphone slowmo video the launch and just pay attention to the little things. Don’t spin the tires while sitting in the water. It slings water up in the wheel house to rain down on the tire. Pull around the water and back into it. When you pull out of the water avoid the puddles that collect in the ruts right in front of the water box. Offset left or right to stay out of them. The tire is not your limiting factor at this time.