I was able to borrow a BIG carb from a fellow truck puller. It has 2.200 throttle blades. He couldnt remember what cfm it was. But it picked up 6hp on top and areas of 10-20 trough the mid-range. So a big carb did help a good amount. This is at the wheel numbers. 740RRWHP which is on my chasis 1070hp.