[bleucamaro]

A waste gate is for turbochargers, it controls the speed of the turbo by diverting excess exhaust away from the turbocharger.

I think a bypass or "blow-off" valve is what you are looking for. This is vacuum operated, so when you close the throttle, it opens and allows pressurized air to be vented to atmostphere (blow-off valve) or be redirected to the intake tract between the filter air box and supercharger inlet. This valve prevents the engine from surging/jolting.

The easiest way to tune is to size your pulley for the maximum compressor speed you want to run, there are compressor maps and custom sized pulleys available online, but since this was a "kit" it should be figured out for you.