You’ve probably heard the terms “turbocharger” and “supercharger” at some point, but without spending plenty of time under the hood of a car, those terms can be little more than everyday automotive buzzwords.
Turbochargers and superchargers are forced air induction systems. Like the name suggests, they function by force-feeding oxygen into a vehicle’s engine, which increases the amount of fuel an engine can burn, and therefore boosts its power. The key difference between the two systems is how they achieve that goal.
Turbochargers draw their power from the vehicle’s exhaust stream to create more power. The exhaust passes through a turbine that rotates at speeds of up to 150,000 rpm. The turbine turns a compressor that draws more air into the engine, allowing more fuel to be burned for more power.
An example of how much power a turbocharged engine can offer is the Ford Focus RS. The Focus RS has a turbocharged 2.3-liter four-cylinder engine that delivers 350 horsepower and 350 pound-feet of torque.
Unlike turbochargers, superchargers use a belt that is directly connected to the engine’s crankshaft. The supercharger draws more air into the engine’s combustion chamber to deliver a boost to the engine. The increased airflow to the engine allows more fuel to be combusted and can increase the vehicle’s horsepower by about 50 percent.
One of the most powerful vehicles currently available with a supercharged engine is the Dodge Challenger Hellcat. The Hellcat’s powerful 6.2-liter V8 engine produces an incredible 707 horsepower.
Both systems deliver additional power to a vehicle’s engine by drawing more air into it, but they have their trade-offs.
A vehicle equipped with a supercharger delivers power very quickly and at a lower rpm. But the earlier boost delivery can result in a lag later on. Superchargers are very easy to maintain, easy to install, and reliable. But they also tend to be noisier, less fuel efficient, and more expensive.
On the other hand, vehicles equipped with a turbocharger might not experience the boost in power until the vehicle reaches a certain speed. This brief delay is known as “turbo lag.” However, turbochargers are quieter and more fuel-efficient than superchargers, because they're using the energy from the exhaust flow, which would normally be wasted.
Why Is Either System Necessary?
Getting more power out of a vehicle is a top goal for many automotive buffs. The easiest way to get more power into a vehicle is by installing a bigger engine. But while a bigger engine can provide more power, they cost more to produce, weigh more, and offer lower fuel efficiency, which is why many automakers have been using smaller engines instead.
These smaller engines are still capable of delivering plenty of power, but they need an assist to do so. That assist can come from a turbocharger or a supercharger, which force oxygen into the engine to add more horsepower.