I also had the same problem on my Dart with a hemi scoop took it to the track with a dominator on top of 2" adaptor and victor intake, did 3 runs, first was 121, so i jetted up a couple, the next 2 were 122, on the same day i swapped my old 950 with 2" supersucker back on and it picked up 5 mph the next 2 runs. Ran the car without the hood next time out with the dominator back on and it ran it's best ever speed.
Mick