Boost of any kind isn't directly related to RPM. Boost is more closely relate to load and total engine restriction. Full throttle and 3000 RPM holds more boost than part throttle and 3000 RPM because the load isn't the same. Reduce restriction after the boost device, boost goes down, yet HP goes up, even though the load and RPM stay the same. These hold true to either SC or turbo...
Want more boost a low RPM? Get a turbo that spools up faster (either smaller in size or just more efficient), or put a smaller pulley on the SC to spin it up faster. You can make an SC achieve max boost at 2700 RPM too if you want to. Although the boost devices are not directly related to engine RPM, they are direcly dependant on their own RPM to move air. The fan trim size and shape being equal, the turbo and SC will move the same amount of air. The SC losses power through it's drive belts and pullies, the turbo through it's exhaust restrictions. Drive either without the input tube hooked up and boy, do you know it!!!
The silly part is, everyone is hashing the exact same points here.
