Centrifugal superchargers aim for max boost at the high end
A centrifugal supercharger is basically the same type of pump as the compressor side of a turbocharger, but is mechanically driven off the crankshaft instead of by exhaust gas. Internal gearing steps up the spin speed, and gives a distinctive whistling sound, that most drivers enjoy hearing, but the centrifugal supercharger must be classified as noisy. мавит, вибротон и ирригатор, самоздрав, алмаг, магнитотерапия и дарсонваль
The centrifugal's type of compressor - like the turbo's - is efficient only at high rpm. Because all superchargers by definition are under continual drive from the crank (i.e. with no comparable turbocharger wastegate system to cut the drive), design decisions set the limits to how much internally to gear-up (overdrive) the spooling: the centrifugal aims for high-end boost and in consequence gives almost none at low rpm.
Centrifugal superchargers build boost relative to engine rpm: boost builds exponentially in the upper half of the powerband - generally they start boosting around 2000 to 3000 rpm, and attain full boost at max rpm - i.e. the quoted maximum boost of a centrifugal happens at redline.
Enthusiasts say that in situations where they demand performance from their vehicle, they spend most time in the mid to high rpm ranges.
Best applications of centrifugals
The centrifugal is good for lightweight, manual transmission (downshift for higher rpm) vehicles, and popular with muscle cars that have plenty of low-end torque already, but not so good for heavier vehicles under load or towing, or automatic transmissions - in these cases a positive displacement supercharger is more suitable (see our Roots Superchargers page and our Twin Screw Supercharger page).
Centrifugal superchargers are generally cooler than turbochargers, with adiabatic efficiencies in the 60-80% range (see our Supercharger Heat page for more about heating and cooling of forced induction systems).
All superchargers generally are less complex to mount than turbos. As aftermarket modifications superchargers tend to be cheaper to install and generally cost less to service and maintain.
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