Hmmm, I have a pro-systems HP1000 on my car and after a pass on the drag strip and letting off the car seems to flood. If I just hit the brakes and turn off I have to feather the throttle a little as it acts like it is flooding out. I tried a hose between the bowl vents and this did not change anything. The quicker I brake the worse it is. We have a pretty short shut down area, if I coast out to the next turn off it is better. But seems quite strange to me. Seems quite similiar. I almost bet yours was flooded, because I believe you would have felt it run out of fuel earlier. After coasting those bowls should fill immediatley at the high rpm and no fuel demand.