What is the difference between a supercharger and a turbocharger in a vehicle’s engine?


Turbocharged engines seem to be much more popular in recent years, especially on smaller engines. How does a turbocharger “turbo”, and what is a supercharger?

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Turbochargers use exhaust gasses to spin the compressor, superchargers use a belt run off of the engine to spin the compressor. Both use a compressor to increase the density of the air being sent to the engine which in simple terms, creates more powah.

A turbocharger is a fan powered by engine exhaust that compresses extra air into an engine intake. A super charger is not powered by exhaust, but by the engine itself or even electrically powered. Turbochargers have an inherent lag while superchargers are a bit faster. Turbochargers are more fuel efficient, while superchargers are faster with generally higher performance.

Both devices compress the air going into the engine which makes it more explosive. A turbocharger uses the engine’s exhaust gasses to drive the rotation of the impeller and a super charger uses a belt driven by the engine’s crankshaft.

Turbochargers use the exhaust gas to spin a high-speed turbine, which compressed air before it enters the combustion chambers. Superchargers do the same thing but are powered directly from the engine. Superchargers therefore give the benefit of compressing the incoming air whenever the engine is turning; turbochargers lag behind a little as they need a reasonable flow of exhaust gas to start working.

A turbo charger is an impeller which takes cold air and “packs” it into your air intake, increasing the air pressure in your cylinders. More air = more kaboom = more vroom. The turbo’s impeller is driven by exhaust gas in a feedback loop, so there’s a little bit of a lag behind when you step on the gas and when the turbo kicks in, because the cylinders have to exhaust the increased output to drive the turbo to boost the air intake to drive more cylinder combustion.

A super charger does the same thing: packs more air into your combustion cylinders – but its not driven by exhaust gasses, its driven by the same rotating mechanical bits that the pistons in your cylinders drive. The feedback is more immediate, there’s no turbo “lag”, but it comes with a more severe parasitic drain on your engine’s output. Say 10%. But its giving your engine a 20% boost, so you have net 10% more power coming out of your engine.

Meanwhile turbo penalties are less, like 5% but they maybe don’t contribute as much performance gain maybe only 10-15% percent, so you’re net 5-10% performance boost overall.

There are pros and cons for each, and you can even use a turbo and a super charger together.