Make sure it is not sticking in 2nd gear, mine did that a few times whe nit was brand new and it was slugggish because starting in 2nd. Richen up the top end needle again ,then lean it out till it runs good a full throttle , then go to the low end needle and try richening it up and leaning it out and see where it runs best at. The botttom end needle is going to change the off the line power. My 3.0 took me a little while to get it perfect, but now it is crisp off the line.......Hope this help.......