Frequently Asked Questions

What is the difference between a turbo-charger and a super-charger?
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Supercharger Turbocharger
Let's start with the similarities. Both turbochargers and superchargers are called forced induction systems. They both compress the air flowing into the engine The advantage of compressing the air is that it lets the engine stuff more air in a cylinder. More air means that more fuel can be stuffed in too. Therefore you get more power from each explosion in each cylinder. A turbo/supercharged engine produces more power overall than the same engine without the charging. The typical boost provided by either a turbocharger or a supercharger is 6 to 8 PSI. Since normal atmospheric pressure is 14.7 PSI at sea level, you can see that you are getting about 50% more air into the engine. Therefore you would expect to get 50% more power. It's not perfectly efficient, so you might get a 30% to 40% improvement instead. The key difference between a turbocharger and a supercharger is its power supply. Something has to supply the power to run the air compressor. In a supercharger there is a belt that connects directly to the engine. It gets its power the same way that the water pump or alternator does. A tuborcharger, on the other hand, gets its power from the exhaust stream. The exhaust runs through a turbine which in turn spins the compressor. There are tradeoffs between both systems. In theory a turbocharger is more efficient because it is using the "wasted" energy in the exhaust stream for its power source. But turbos have what you call turbo lag too... it is the time it take the turbo turbine to turn. On the other hand, a turbocharger causes some amount of back pressure in the exhaust system and it also tends to provide less boost until the engine is running at higher RPMs. Superchargers are easier to install but tend to be more expensive. Thanks to "How Stuff Works" & Krazy for this information.