Just a reminder to everyone, be civil. <img src="/forums/images/graemlins/smile.gif" alt="" />

Litin said it, but not exactly. The concept is to compress the air before it enters the engine. A super charger (screw or centrifugal) and a turbo both compress the air within their housing before putting it into the intake. We call them blowers, but they really are compressors. The thing on ebay is most likely a boat exhaust fan. Fan, fans blow, but are very poor at compressing anything.

Other things to remember is a) you put a boat fan in your intake tube and it is going to be a huge restriction. It will restrict when it is on, it will restrict when it is off. b) I also doubt it can even come close to moving the required CFM for an engine. c) as Litin said, anything electric that has the ability to move and compress air will require a large amount of juice to run. Not to mention that your alt may put out x-amps peak, but that is only at a certain RPM, what happens when you are not in that range? Well, any electric motor that is run with insufficient amperage will just burn up.

Good Luck,
Michael