Wow. That stall is way off. My guess is 6200-6800 would be a better place for you. Is it an 8 inch or 9 inch convertor. Sounds like you are driving right thru that convertor. What carb, cam, etc. We launch our swingarm at 4400-4600. It is a 548 with a 5800 stall single 1050 alky carb. It runs short time of 1.16 and runs 5.0's 4.90's with a 6600 shift. Where you shifting at?