""Are you using a toothed external drive ?""
The external drive belt is a 6 rib serpentine type belt.
Here is their website and propaganda.
www.powerdyne.com
and
http://www.powerdyne.com/silentdr.htm
They are not willing to help, just keep saying "Send it back to...
I have had a Powerdyne Supercharger with an internal belt drive similar to a Cam drive belt on OHV engines. The belts seem to break due to both heat and tension. I have tried Kevlar belts, which seem to last longer, but still break. I have heard that Neoprene rubber is only good to 150* F...