Garrett Turbo

Bond Mejeh asked:


Supercharging and turbo-charging your engine will get you the same thing: more horsepower. Both work by increasing the amount of air that goes into the combustion chamber, resulting in a more powerful explosion. However, they both do it in very different ways.

A supercharger works by taking power from the engine via a belt/pulley system. The belt turns an impeller inside the supercharger that forces more air into the combustion chamber. The benefits of having a supercharger, is that it’s very straightforward to use, and the power is there whenever you need it. Also, a cool feature about it is that it doesn’t require special cooling or maintenance. It’s easily more reliable than turbochargers.

A supercharger also provides a smooth boost throughout the entire power-band, which results in more predictable handling and power at low, as well as high RPM’s. The downside of supercharging is that it uses a small amount of power from the engine all of the time (because of the pulley). Ironically, the more power the supercharger produces, the more power it pulls from the system. But the net result of having a supercharger would most likely turnout better than not owning a supercharger at all.

A turbo charger works much like a supercharger, where it forces more air into the combustion chamber. However, instead of being driven by a pulley/belt combo attached to the engine, the impeller is spun by exhaust gasses from the engine. When the engine is at rest, the turbo charger impeller is idling, because there is little pressure in the exhaust that is released from the engine. As the engine is revved, more exhaust pressure hits the turbo charger’s impeller causing it to turn, which puts more air in the combustion chamber, which also increases the exhaust pressure by hitting the turbo impeller. Hopefully you can see where this is going at this point. The faster you go the more power the turbocharger produces.

The benefits of having this type of system, is having a lot of power being produced with no extra effort on the engine’s part. You can also increase the air density by adding intercoolers, which cools the air before the turbo gets put into the combustion chamber that allows an even greater increase in power. Another great aspect of owning a system like this is the ability to change the amount of boost available. With some models this can even be done while driving, allowing you to fine-tune the power you need.

However the big con of the turbo charger is the uneven power-band. At low RPM’s the engine is not producing enough exhaust pressure for the turbo charger to add power. This is known as turbo lag. Once it gets going though, it’s a very massive boost. So massive, in fact, that a poorly, setup turbo charger can be dangerous: the sudden and dramatic increase in power can cause the handling characteristics of the car to change. This was especially true of the older Porsche 911 Turbos, which had a habit of swinging the back-end out if you weren’t aware when the turbo boost hit. The other con of the turbo charger is its maintenance. There are more moving parts than in a supercharger, and some models require cool down time after heavy use before the engine can be shut off.

Superchargers are better used for the daily driver who wants a little more power in their engine without sacrificing the reliability or worrying about sudden amounts of power causing a spinout. In fact, there have been mini-vans that have come standard with superchargers, attesting to its same power. Turbo chargers are better used in sports cars, whose handling can accommodate the sudden change in power, where whose drivers are willing to sacrifice some reliability for a large increase in speed.



H Pittman

Eric Ferguson asked:


If you’re interested in adding power and performance to your ride, no doubt you’ve considered adding a turbocharger (just turbo to tuners), or a supercharger to your ride.  However, it can be difficult to determine which is the best for your needs.  For instance, what is the peak operating range of a turbocharger, versus a supercharger? How much horsepower can you gain from each and which is more cost effective?  Here are a few answers to your myriad of questions.

First, you need to understand how each system operates, before you can make an informed choice.  Both turbos and superchargers are a form of forced air induction.  In other words, they provide boost by forcing more air into each cylinder.  More air means more fuel can be dumped in, resulting in larger explosions, more rapid explosions and greater speed.  Basically, they provide more air, which results in longer, cleaner burns.  You waste less fuel, and go farther, faster.  However, that’s where the similarities end.

Turbos:

Turbochargers operate on spent exhaust gasses.  These gasses enter one half of the turbine, propelling the turbine and forcing compressed air into the engine.  The drawback to this method is that the air is very hot (use an intercooler to combat the heat) and the turbo operates at a fairly high RPM rate (75K to 150K RPMs).

Superchargers:

Superchargers are a little different from turbos.  Unlike turbos, they do not operate on exhaust gas.  Instead, they use a pulley and the belts on your engine to drive the impeller, rotating screws or rotors.  This forces air into the engine, providing more boost for your ride.  Superchargers operate at a lower RPM rate than do turbos (anywhere between 15K to 40K, depending on the type of supercharger).

That’s all well and good, but which is better, you ask?  That depends on what you want.  Both systems cost approximately the same (there will be a few dollars difference, but not much).  However, superchargers experience much less lag than do turbochargers. This results in more immediate power.  However, turbochargers can provide more boost at higher rates of speed, meaning that you get more out of them at higher RPM ranges.

Turbochargers also create more boost surge, which can damage engines, as well as creating additional backpressure that must be forced out through the headers.  Superchargers produce more noise than turbos, but are generally longer-lived, providing you with a longer lasting performance enhancement.

In short, it comes down to personal preference.  Both devices provide an amazing boost to your engine performance, knocking your speed capabilities up dramatically. Both systems have pros and cons associated with them, as well.  You choice will also depend on your usage.  For instance, a supercharger is ideal for a street machine, but if you are going to the track, a turbocharger offers better benefits. Before choosing either system, you will need to define your needs, as well as any future use of your ride, in order to make the best choice.

 



Calvin