this blower is off a DART engine, a TURBOPROP i believe, not a piston jobbie. driven off an auxillary gearbox on the engine, it blows from atmosphere to the cabin via filters. used on HS125's, HERALD's and i think... VISCOUNT's... oldskool! i have done a few calculations and i reckon when the engines flat out at 6.5k or 7k the charger will only be revving at 4.5k due to its physical size. i hope that by driving it at low speed like this will create low drag on the crank but still get boost. its designed to flow 750CFM at 10000rpm, obviously this is just not appropriate for the cvh design, hence lower drive speed. why does mild boost not matter at idle speed? wont it run lean? only thing is... does anyone know if i'll have to re jet for this?