THE ROOTS OF SUPERCHARGERS IS RATHER INTERESTING STUFF.
The supercharger's story starts in the 19th century, long before supercharged cars were a thing. In 1860, the Roots brothers developed the first practical supercharger. They weren’t aiming at performance cars; instead, they created it as an industrial air pump for blast furnaces. However, the idea of cramming more air into an engine caught on, especially when Gottlieb Daimler, one of the pioneers of the internal combustion engine, patented the first supercharged engine in 1885. This means the Roots blower was one of the first types used in automotive applications and it’s quite basic in the grand scheme of things. It consists of two interlocking lobes that spin together and force air into the intake manifold. Even though it’s an old design, it’s still used because it provides instant power. The downside is that it’s not the most efficient way to do things thanks to its size, location and susceptibility to heat soak. Roots superchargers became famous in the 1930s when they were bolted onto Mercedes-Benz engines like those found in the legendary SSK roadsters from that era that used to dominate race tracks. They have a signature whine and helped make huge power, especially for the time. And then there’s the twin-screw superchargers, the Roots’ cooler cousin. A twin-screw supercharger looks similar to a Root-type, but its internal mechanics are more advanced. Instead of lobes, it uses two screws that compress air inside the supercharger housing itself, making it more efficient and less prone to heating up the air, the result is that this design gives a smoother power delivery across the rev range and is able to support much higher boost levels. Twin-screws were first used in high-performance vehicles in the mid-20th century but things really took off with OEM applications in the '90s in cars like the Mustang SVT Cobra.
Centrifugal superchargers can sometimes be mistaken for a turbocharger thanks to the way they look, well that or an upgraded alternator - the latter being the excuse that husbands tell their wives about the new shint part under the hood. “Hey honey, that’s just an upgraded alternator so that the aircon works better in summer”. Roots and twin screws are directly connected to the engine and provide boost immediately, but centrifugal superchargers act more like a belt-driven turbocharger. They use a spinning impeller to compress the air, similar to how a turbo works, but instead of being exhaust-driven, they’re driven by a belt connected to the crankshaft. These things gained popularity in the ‘80s and ‘90s thanks to better efficiency and a lighter overall weight. They don’t have the same low-end boost as a Roots or twin-screw, but they’re excellent for high-RPM power, and most modern cars like revs. These are commonly used in aftermarket kits and they offer great performance while being relatively easy to install, many kits come with an easy-to-follow step-by-step guide and even those with a mere YouTube certification in mechanics could fit a kit in a home garage over the course of a weekend. Superchargers took off in motorsports in the early 20th century, where they played a key role in Grand Prix racing and land speed record attempts. Throughout the ‘30s, cars like the Bentley Blower and the Alfa Romeo 8C 2300 used Roots-type superchargers, in the 1950s, American automakers started experimenting with them on street cars and things haven’t slowed down since. These days superchargers have started making serious waves again, especially in muscle cars and high-performance exotics. Mercedes-AMG had its Kompressor series of cars (kompressor is German for supercharger), and Jaguar Land Rover also loves their superchargers with twin-screw setups in cars like the F-Type SVR and Range Rover SVR. Ford and Chevrolet have had an ongoing supercharger rivalry for years, and that competition sees constant design and material improvements. For more on the subject, check out the link below.
Take a look at the YouTube video from the chaps at The Engineers Post that explains just how these other boost-makers work and what the differences are, and they even add in a bit about the new electric ones that we didn't mention because we're not fans: Superchargers Explained | How Different Types of Supercharger Works? | The Engineers Post
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