A longer, wider belt will provide a lower initial gear and a taller final gear. I did not do back to back measured tests to find out exactly what the gains were. Top speed is power limited, not RPM limited anyway so there may be no increase in top speed. What I mean by power limited is that the engine does not have the power to pull a higher speed with higher gearing. I hit 75 on GPS with 20" tires. 22" tires do not add any speed and 24" tires make is slower, most likely due to the rotating mass. So you'll probably only see real world results with the wider belt on the the take off performance.
I am also running Heel Clicker cam arms in my clutch. They allow having a lower engagement RPM, yet still pull harder off the line than standard cam arms.
