Truth be told I really only experience the flat line at about the 1000ft mark at the dragstrip. Felt like the car just ran out of gas. Didn't stall or anything but just kinda gave up. Other people have had the same type of issue in the top of lower gears but that could be caused from not having enough fuel in the tank and the pickup becoming uncovered or just a small fuel bowl on the Qjet going empty. I did also run into lean conditions while on the dyno so I know it's real. I currently run two pumps. One electric and one mechanical. So far so good. I haven't really thoroughly tested it yet though.