If you have a need for speed, then supercharger and turbocharger are words you’re probably quite familiar with. But you may not know that they are not exactly the same thing. Yes, they both provide more power and speed to your vehicle. Yes, they both use power from the engine to increase the engine’s power, as redundant as that sounds. They just do it in different ways. As similar as they are, there are positives and negatives to both.
We’ll start with the similarities in both systems. Both systems are known as “forced induction systems.” This means that they compress air which flows into the engine and allows for more compression in the cylinders. More air in the cylinders also means more fuel in the cylinders. More of both these elements allows for a higher rate of combustion which, in turn, provides more horsepower. The amount of boost they each provide is also similar. It varies between six and eight pounds per square inch (psi) for both devices. Normal atmospheric pressure is 14.7 psi at sea level. This means you’re getting up to fifty percent more air into the engine cylinders.
The other big similarity between the two systems is that they are both powered by the engine itself. In supercharger systems, that power comes from a belt. It receives power in the same way your water pump and alternator receive power. Sometimes the supercharger has a belt of its own, other times it runs directly off the engine’s serpentine belt. A turbocharger gets its power from the exhaust stream coming from the engine. The exhaust stream runs through a turbine, which powers the turbocharger compressor. In essence, it’s just one big cyclic system.
Ironically, the similarity that they are both powered by the engine is also one of the biggest differences between the two systems. They’re different in the fact of which part of the engine gives them their power. The belt running the supercharger is run off of the crankshaft. This means your engine is working to provide itself with more power. The air powering the turbocharger is run from exhaust being put out of the engine. In that respect, the turbocharger is actually slightly more efficient. It is using the “wasted” energy that’s leaving your engine and converting it to added power. Contrarily, it also increases the amount of back pressure in the engine. This means that a turbocharger will tend to provide less boost until the RPMs of the engine are higher. Superchargers maintain their level of increase throughout operation.
If you’re not getting either of these systems fresh from the factory, turbochargers are also more difficult to install. Superchargers are typically more convenient in their installations, but they also tend to cost more. If you’re getting either system direct from the factory, then the choice you’ll have to make is where you want the most increase of your power. Do you want the increase at higher RPMs from a more efficient system? If so, the turbo is your answer. Or, do you want a steady increase at all speeds, sacrificing a little extra drain on your engine?
No matter which way you go, you’re going to get at least thirty percent more power from the system, and typically that will range closer to forty and fifty percent depending on rpm and engine size. One is belt driven and one is turbine driven, but they both end up stuffing more fuel and air into your engine, which gives you that little extra heart-racing kick right when you want it most.