holley help...

[camshaftgsxr]

355/700r4 with a holley (who would think i would have any problems huh?) from cold start to warm throttle response is amazing in neutral but when its in drive it doesn't wanna accelerate at all just stumbling and falling all over itself, even when the rpms are up at 2000-3000 it won't speed up even with very little throttle, the carb is a 600cfm holley with only about a thousand miles on it, i have done manifold vacuum tests and adjustments and other things but nothing, i watched the holley instructional video on carb tuning and i tried to get it dialed in but no help... any suggestions

thanks peoples