What is a Supercharger & What Does it Do?

A supercharger is an engine device designed to force as much air as possible into the combustion chamber. This increased airflow allows for more fuel to be mixed and ignited, resulting in a significant boost in power output. Unlike turbochargers, superchargers are powered directly by the engine, thus providing an immediate power boost with minimal lag. The surge they deliver is instantaneous and accessible across the entire RPM range.

While various types of superchargers deliver power differently, this characteristic generally applies to all. Furthermore, the distinctive mechanical "whine" of a supercharger is often considered one of the most captivating sounds a car can make, providing ample reason for enthusiasts to install one.

The Different Types of Superchargers 

There are three types of superchargers that are used in the automotive world:

Roots-type Supercharger

The Roots-type supercharger, a design dating back to around 1860, functions as an air accelerator by forcefully directing air into the intake manifold. 

However, it faces efficiency challenges as the temperature rises. As RPMs and pressure increase, the power output diminishes, leading to a decline in performance at higher revolutions.

Centrifugal Supercharger

Operating as air compressors, centrifugal superchargers generate power based on engine speed. Although they offer boost at low RPMs, the increase isn't significant. These superchargers function similarly to turbochargers by enhancing boost and power as the engine speed rises. 

Unlike turbochargers, centrifugal superchargers eliminate lag between acceleration and power, providing a smooth and steady power increase as they reach optimal speed and generate more boost.

Twin-screw Supercharger

This supercharger functions as a compressor, delivering consistent power from idle to redline. The advantage of a twin-screw supercharger is its ability to provide full output even at low revs, with no power drop-off throughout the rev range. This is partly because it operates cooler than a Roots-type supercharger. 

However, these superchargers are complex pieces of equipment. Systems supporting a twin-screw supercharger must be precisely engineered, leaving no room for error. Consequently, they result in a more expensive power delivery system compared to the other two types of superchargers.

If your car is having problems and you suspect it’s the supercharger, don’t hesitate in booking in with a Performance Specialist on AutoGuru. A fully qualified, local mechanic is the best person to figure out your supercharger woes.