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?
In: 4
All engines ultimately boil down to the fire triangle that most of us learned about in school. The three points are air, fuel and an ignition source.
In a car that’s air, gas, and a spark. If you want an engine to make more power you can increase the air (and the fuel) and it will make a bigger bang.
Both Turbos and superchargers increase the air that gets taken into the engine, they just do so in different ways.
Turbos and superchargers are really both fans. Those fans suck in air and push the air into the engine, this is known as boost. It means more air gets into the cylinder and when combined with extra fuel it makes the car have more power.
Now, in order for a fan to suck air into an engine, the fan needs to be spinning. In order for the fan to spin it needs to get that that power from somewhere. You could use electricity but that’s actually pretty inefficient on an internal combustion engine.
So other than an electric fan, there’s 2 main methods. There’s a power take off, meaning the engine itself spins the fan. This is the same system that runs the coolant pump, AC, or car electrical system. The engine has a belt, and in addition to making the wheels turn the engine makes the belt go around (using a pully). Then a bunch of accessories attach to that belt and the belt powers them all. In most cars this belt is right at the front of the engine and can be easily seen if you look down in the front of the engine compartment.
A supercharger is a device that also runs off that belt. Basically this is the engine powering it’s own fan and generating even more power. This has plusses and minuses, mainly it’s easier to add big power this way but it’s not super efficient. It’s like taking away 10 units of power in order to add 20 units. It’s a net gain of 10 but the engine is burning more than 10 units of fuel in order to get there.
Turbo chargers are a little more smart. A turbo uses the engine’s own exhaust to make the fan spin. Think of a water wheel on a river. The river is the exhaust being pushed out of the car, the turbo is the water wheel. the exhaust is going to be moving out of the engine with or without the turbo, so the turbo just takes some of that energy and uses it to spin the fans. Therefore there’s no extra load on the engine.
The problem with turbos is heat. Exhaust gases are REALLY hot when they leave the engine. That heat is bad for everything, but mostly it’s bad for anything that has moving parts. Like a turbo. So a turbo has a lot of stress on it because it’s dealing with super hot engine exhaust. So while turbos are more efficient than superchargers, they are less reliable because of all the problems that heat causes.
So both methods make the car go faster by adding extra air into the combustion. They just do so differently and both have their advantages and disadvantages. It’s more common to see a turbo in a car than it is to see a supercharger but that’s more about meeting fuel efficiency standards than it is about turbos being inherently better or worse.
Latest Answers