Car is DC Hoover motor is AC, what is your convertor? is it an invertor?
Yes use fuse's and have a fire extinguisher near by

You can actualy buy 1500cfm 12v DC impellors from RS/Trade specialist suppliers which will fit into the front of an 8v air box, i have measured it (Just like a large computer fan).
This draws 80amps from the battery and can be controlled like electric Electric S/C kits from the go pedal.
Best bet is to buy Mikesters spare 8v lump and fit it into your boot and call your golf a valver
