Pressure vs. Volume is something a carburetor is dependent upon for proper operation - PRESSURE DOES NOT EQUAL VOLUME. Generally speaking, as pressure increases through a needle and seat assembly the volume will decrease. Increased fuel pressure leads to issues like aeration, fuel spray and starvation. One thing we like to remind people of is the fact that your float has to overcome whatever your fuel pressure is - if your fuel pump and regulator are set to 10psi, then it will take 10psi to shut off the needle. Some float designs are not capable of this, combined with a shortened lever and the problem just compounds itself.
We recommend setting your fuel pressure to 6.5-7.0psi for best performance.

Proper float level on a Quick Fuel Technology carburetor is set with fuel pressure generally falling between 6.5-7.0psi. Once you are certain of your fuel pressure, then it is a matter of adjusting the float height using the adjustment nut. Start by loosening up the lock screw (turn counter-clockwise) by a half-turn or so to free the adjustment nut. Once free, move the adjustment nut to raise or lower the float - clockwise will lower the float, while counter-clockwise will raise the float. With proper fuel pressure, the fuel level should be about halfway up the sight window - once satisfied with your float level, don't forget to tighten the lock screw and wipe away any excess fuel.