How does a turbo work on a car? And what’s the difference with a supercharger?


How does a turbo work on a car? And what’s the difference with a supercharger?

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I’m not a car enthusiast nor an engineer but will explain the best I can. A turbo charger uses the vehicles exhaust to turn the turbine (that’s why turbo lag) and a super charger uses a belt to turn the turbine.

They both provide more air into the combustion process by compressing the intake air, thereby allowing more fuel to be introduced as well. The major difference is a “turbo” (which technically is a supercharger) uses exhaust gases to drive the compressor, while a supercharger is belt driven

Okay so more air means more fuel burns which means more power. Think I’m getting it, thanks!

A turbo consists of two turbines connected together on the same shaft. One is connected to the exaust manifold and uses the force of the exhaust gasses to spin the turbo. The other turbine is connected to the intake manifold and uses the energy provided by the exhaust gasses to force fresh air into the cylinders. This means that the cylinders do not get slowed down when sucking air into them. They are even able to provide pressure to force more air into the cylinder then there is normally room for which increases the effective volume of the engine. The cost of this is that it does slow down the cylinders a bit as they force the exhaust gasses out but the gains are much higher then those costs.

A supercharger does the same but is connected directly to the engine output instead of scavenging energy from the exhaust. This means they have a bit different design due to the difference in speed and also end up reducing the power of the engine more then a turbo. However a supercharger is much faster at changing speed and works much better at lower speeds then a turbo. This does give lower lag and better low end torque then a turbo. Hence a supercharger tends to be better for a few types of racecars. It is also used in two stroke diesel engines. But the higher efficiency of a turbo means it is most common now.