WHAT IS A SUPERCHARGER?
Superchargers are actually easier to understand than turbochargers, but given the popularity of turbocharged cars in the UK people are often more familiar with turbos than they are with superchargers. So, thinking of it like a turbo, a supercharger basically does the same thing, but rather than being powered by exhaust gases spinning a turbine, a supercharger is powered directly from the engine’s crankshaft, usually via a drive belt.
There are three main types of supercharger; Roots-type, centrifugal, and twin screw. All work in a slightly different way, but ultimately they all do the same thing – compress the intake air and force it into the engine at a higher pressure. And because the speed at which the supercharger operates is directly linked to the engine rpm (remember the supercharger is driven by the crankshaft) there is no need for complicated boost control. Instead engine rpm and simple gearing can control everything. Simply by using smaller or larger diameter pulleys you can cause the supercharger speed to increase or decrease accordingly.