[hawk2100n]

Originally Posted by Christ

Roots blowers generally use a helix type rotor design to help smooth the pulses out. Only very old designs use "impulse" style charging, because it creates a pulse frequency that can make proper fueling very difficult.

Thus, there's really no way to "time" the pressure pulses exactly to a specific event, since the design is meant to provide steady pressure, rather than pulsed pressure.

Even if you designed a blower that provided pulses, it would only serve to enhance the effects of helmholtz tuning (frequency-based freeair supercharging), and wouldn't provide much of an efficiency gain over just charging and maintaining pressure in the intake tract.

Purely hypothetetical. But yes I would specify a roots blower instead of a screw type. But who knows what it would do. You would only have a slight gain over a similar setup at the resonant frequency. Really none of this applies because superchargers don't improve efficiency but power. The work I have done with engines is in the racing sphere and that is very different than efficiency. Max power has been driven into my head.