Haha... yeah, I've seen these things floating around for years. The classic "hairdryer supercharger". I remember ranting on these things on Usenet back in the day
Seriously... do you know how much air an engine actually swallows? If you do the math and figure out the volume of air you have to push into the engine to overcome the blockage you've just created by putting your "hairdryer" in there and then pump MORE air into the intake, you find that the power requirements for said motor must be ridiculous in order to provide any gains at anything above idle. Once you factor that power has to come from SOMEWHERE, you've then also got to install a much bigger (and draggier) alternator to provide the power, then up the boost in order to overcome the parasitic losses... and then you have to figure the volume of incoming air all over again. Ad nauseum. Etc.
There's a reason that mechanical superchargers work well; they don't suffer from energy losses through heat to nearly the extent that electric motors do. As a result, their efficiency is FAR higher than any electric motor could hope for... plus it's pretty much directly attached to the engine for almost zero loss of torque from the turning engine. Turbos work because it's "free energy", i.e. energy that you're throwing out the back of the car already.
I have never actually tried one, but every time I've seen these things advertised I just whip out my calculator and pocket protector then laugh
