Forced induction

Lovert Mafukure

An avid follower of our column asked an interesting question, they asked what the purpose of a turbo is and if there’s any effect removing it if you car is equipped with one? As usual we need to understand what a turbocharger is and its purpose on a car as some cars have them and some don’t. Simply put, its something that blows some magic into the engine to make it go fast.

Natural aspiration, forced induction, turbochargers and superchargers — pretty much part of our topic today. An engine is like a pump that naturally sucks air from the atmosphere for combustion purposes, its intake only depends on normal atmospheric pressure — in fancy automotive terms that is called natural aspiration and it is the opposite of forced induction.

After the invention of the engine, scientists later discovered they could get more power out of an engine if they force-fed it and then forced induction was born.

Forced induction means the engine seizes to suck air by itself and is force-fed, it makes use of a compressor to force air into the combustion chambers. That’s the simplest way to put it.

Over time scientists also discovered that by forcing air into the engine, they could increase the amount of fuel that goes into the engine and subsequently increase the power output of an engine.

That is why you find four cylinder engines with serious power outputs that send V8s into hiding. To get more power from an engine, you’d have to add more cylinders, but with forced induction, they realised they could get more power without adding any more cylinders.

There are two types of compressors commonly used, turbochargers and superchargers. A turbocharger is a turbine driven compressor that forces more air into the combustion chamber. The result is more power output as I mentioned. Exhaust gases drive a turbocharger, the turbine in-turn drives an air compressor that forces more air into the combustion chamber allowing for more air and fuel to burn.

A supercharger is essentially the same technology but the difference is that it is belt driven and not driven by exhaust gases. They depend on engine speed and don’t have lag like turbo chargers. Turbochargers sometimes behave like a bow and arrow . . . first you pull to build some momentum then let go. At times you can press a turbo car hard and feel nothing . . . till the turbo kicks in.

Turbochargers are there for some simple reasons, one being more power output for the same engine size. A four cylinder engine that’s turbocharged can produce the same amount of power as a V6 or even more.

That means instead of having a heavy V8 engine, a manufacturer can use a smaller 4 cylinder turbocharged engine with the same output thus reducing gross vehicle weight and fuel consumption.

Engines with turbochargers are normally made stronger than those without so that they can withstand the heat and pressure. You will find that most turbocharged engines have stronger internal parts like pistons, con-rods and crankshafts. That means then they last longer too which is a plus when buying a car.

Coming down to the question at hand, the effect of removing a turbocharger. First of all, it’s not recommendable to remove a turbocharger if your car was originally equipped with one because you will alter its power output.

You will also need to consider that you will be altering the whole intake and exhaust system of your car. It may also mean that you will have less air going into your engine.

If it’s a diesel car you may end up burning more diesel than the air available. You will end up with black smoke from your exhaust. With modern cars that are run by computers, your car may never run well since it would have been tuned to work with forced induction.

It is advisable to repair or replace the turbocharger if and when it fails. If it keeps failing, you need to make sure that it is well lubricated and there’s no foreign matter being sucked in. Keep your car well serviced to ensure your turbocharger lasts long. Regular oil and filter changes are necessary for the life of your turbocharger.

They are very expensive to fix or replace so it is well worth your while to make sure your car is well maintained so that your turbo lasts long. Removing it is not the best if you want to enjoy your car the same way as it was when it came from the factory.

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