#8 line to the Reg. ?
#4 or #6 to each side of the carb?
High flow needle and seats?
Floats adjusted to low....
Sounds like your saying the car is "Noising over"
Or dose it just do the hucky-buck if you keep your foot in it?
And I would say....turn the limiter up for 1 pass to check it... Tach might be reading wrong?