I dont get it. Maybe because Ive never checked one out in real life.

Ive always figured with a turbo, the fan spins and condenses air together, then some door thing opens and the air shoots to the intake. Yes?

Is that how a supercharger works? I notice belts, such as our A/C PS belt, dont spin that fast. So I doubt the spinning leading to a fan moves that much air, it must condense it? Just looking for a good explanation

You have got to be kidding right?
http://www.howstuffworks.com/turbo2.htm
Turbo's work off exhaust and a supercharger works off a belt....both are the same concept.

>You have got to be kidding right?
>http://www.howstuffworks.com/turbo2.htm
>Turbo's work off exhaust and a supercharger works off a
>belt....both are the same concept.

that's not exactly what he's asking.

but just for the fun of explaining this the 8th time :)
you are talking about how they actually produce power by putting more air into the motor, right?
ok.. well turbo's and centrifugal superchargers work the same on that aspect so I'll just refer to both of them as 'turbo's for the rest of this post.
while 'old style' superchargers or what you see on most V8's and what not are either 'roots' style blower or 'wipple' style blowers, which work mostly on the same principals.. so I'll just refer to them as S/C's.
Ok.. with turbo's, the turbo actually compresses the air inside it's self. this happens by a well designed compressor wheel, as the wheel starts spinning (very very fast, like 60K-90K in rpms, turbo's achive this from the exaust causing it to spin with another wheels, while centrifugal superchargers achive this from a belt drive off the crank and then an internal gear or belt drive that causes it's compressor wheel to spin much faster then the crank). when the wheel finally spools up to speed, it's spinning so fast that it's sucking the air and and actually flinging it into the 'snail' (compressor housing) during this it's forced through a passageway that gets smaller and therefor compresses the air. the compressed air is then blown out the end of the 'snail' into the intake piping and then into the motor.

Now S/C's.. with a S/C, it doesn't actually compress the air inside it's own structure. what they do is just as one of their names suggests (blower) they blow air into the intake manifold faster then the engine can use it up (this is why the are almost always connected to their own custom intake manifold). this causes the air in the intake manifold to compress as it gets backlogged from the S/C forcing it in faster then the engine can use it, creating 'boost'. the S/C works usually from some sort of twin screw screw design (most common) and the screws don't need to spin much faster then the crank (no internal gear or belt drive to make the screws turn insanely fast, cause they don't need to). The size and design of the S/C needs to be properly sized with the size of the car's engine and how high it rev's, which is somewhat the same with turbo's.. but it is much more important with S/C's. example.. I think Jackson racing uses a .6L S/C on the 1.8L-2.0L cars.. while you'll find like 1.5L-2.5L S/C's on big V8's.. it's also kinda where they get the 'positive displacment' name from.
In any case both have their pro's and cons on how they deliver the power and what problems or benifits are achieved from installing either one.
I hope that explains it enough for ya.

and I hope nobody starts posting in here turning this into a damn debate over which is 'better' That would be really F'n stupid since this guy is just asking for the facts on how each system compresses air.

hey thanks for the explanation