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Originally posted by zesmitoda+Oct 15 2004, 04:21 AM-->QUOTE (zesmitoda @ Oct 15 2004, 04:21 AM)
@Oct 14 2004, 09:56 PM
tell me, so i would know too

what difference is between supercharger and a turbo

i have a veery vague idea of what's going under the hood with adding one of those to the car, but in my vague idea there's no difference between these two. so, educate me. please.

I'm not a car expert here, so I won't go into great detail. However, a turbo and a super are functionally the same thing: they force more air into the combustion chambers (ultimately) which results in more power released per ignition. This also results in more pressure obviously which means there's only so far you can push it before you go beyond the limits the engine is built to withstand. Put simply, that's bad.

The difference in a turbo and a super (without looking atanything like power curves) boils down to simply what the device that forces air into the combustion chambers is powered by. In a super, it's driven directly by the engine either through a belt or the crankshaft. Thus the whole phrase "You lose power to gain power." It takes power from the engine to power the supercharger, but the supercharger is putting back more than it's requiring by forcing more air into the combustion chambers. You'll hear this referred to as "parasitic power".

A turbo is driven not off the engine directly but off of the waste gases (exhaust) emitted from the engine. The gases are the result of ineffeciency in gasoline engines (all that heat and movement should have been converted into motion of the crankshaft). The turbo is powered by a turbine that is spun by the exhaust essentially recycling wasted energy which is why people say the turbo is more effecient than the super.

As to the difference in driving experience, you've got me. I have yet to hear a good explanation from people preferring one or the other (other than completely irrelevant things like "d00d, the psssshhhhh sound is soooooooo coo'!!!"). People with supers complain about "turbo lag" (the time it takes to spool the turbine to see power increases/boost) but from what I've read, there are ways of reducing turbo lag. I've heard people suggesting that the turbo wouldn't kick in until like 4k rpm's, but I've also heard from a friend that works on drag cars that turbo lag on a "small" engine such as ours is pretty much nonexistent (but I have no idea as to the veracity of such a statement). Personally, I think it's quite variable, and people are just throwing out super simplified numbers.

People with turbos boast more effeciency and the fact that they can easily add/subtract the amount of boost they're running at (though I don't know how that's physically accomplished under the hood so to speak). With a super, supposedly the only way to increase boost is to change the belts which requires some work under the hood. With a turbo, you can have a "boost controller" in the cockpit and change boost using that.

Anyway, there's the gist of it. Someone can feel free to add on the parts I was vague about (or correct any mistakes in my thinking if there are any). I'd love to hear someone compare the actual driving experience between the two. Like a comparison of power curves. [/b]
turbo lag is determined by a few things, but most importantly turbo size.

Basically on a small engine, you dont want a big turbo. You wouldnt be able to spin the exhaust turbine fast enough to really create any boost.*spin the compressor wheel*

If you wanted a turbo to add some power, but not add a whole lot, lets say go from the stock 160 to lets say 240, you can add a pretty small turbo, t25 or t3 itself which should reach full boost probably between 1800 - 2400 rpms. which is very low.

On my car itself, the turbo will spool *reach maximum efficiency basically* at around 3200 rpms. I opted for this, as my car is fwd. I dont want a ton of power early on, it will allow me to control my launch at the strip a little better. but 3200 is also good because everytime i shift, rpm's do not drop below 3800rpm's so i never fall out of that area.

As he said a supercharger is belt driven, so to adjust the boost level in those, you have to get a new pulley and belt. And then your boost is always set to the same level. With a turbo, you can add a boost controller and adjust it how you want, but its not as easy as it seems either. You can't just change the boost and not be tuned for it.

P.S :p the pssssh sound is way too cool.
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