Turbocharged engines are now becoming more and more common with the stricter emission norms coming into play. Most of the companies are resorting to them now. Why? Because a turbocharger enables you to reduce the capacity of the engine and yet provide similar amounts of power. The only downside is turbolag, which some companies have found a way to work around. Since most diesel cars are turbocharged and there are quite a few turbocharged petrol ones as well in our market, it is important that they are well taken care of. Engineering Explained did a video on five things you shouldn’t do in a turbocharged car. Here’s a summary to it.
Driving hard on a cold engine
Wondering why this point is mentioned since it shouldn’t be done on a NA car either? There is a reason. The temperature gauge on the instrument cluster on most cars shows us the temperature. But that temperature is the coolant temperature and not that of the engine oil. The radiator has a special passage which is used in order to make the car get upto temperature quickly. So when you see that the optimum temperature has been reached on your instrument cluster, it means that your coolant is up to temperature and not the engine oil.
So why do you need the engine oil up to temperature?
When the engine oil is not up to temperature, it flows slowly and doesn’t circulate through the engine fast enough, which means that you are at a risk of low protection. Since the turbo is spinning very fast, it requires lubrication as well. Since we use engine oil to keep the turbo cool, it is important to make sure that the engine oil is up to temperature before driving hard.
How to know that?
Since each car is different, that varies from car to car. However one thing that can be done is to wait a few minutes after the coolant temperature has risen. This will give enough time for the engine oil to come up to temperature and thus will do its lubrication job better.
Not letting the engine cool before shutting the car
In a normal car, this may not be that much of an issue, but in a turbocharged car it can be. When you run the car hard, a lot of heat is generated, especially in the turbo. This heat is sucked away by the engine oil as it acts like a cooling agent. When the engine is shut, oil flow is also shut, which means the oil will not circulate through the engine bay.
So what happens?
Now the oil is in contact with the hot metal parts and isn’t going anywhere. This causes the oil to burn and disintegrate in the long run. This will mean that the properties of the oil will change and they will not be as effective as they were. So now the oil isn’t providing as much lubrication as it used to. This can damage the internal components.
How to prevent it?
Either drive slowly for a short period after driving hard, or idle the car for a few minutes after you are done with your drive before shutting the car. This will make sure that all the components are back to normal temperature before shutting the engine.
Don’t lug the engine
This is something that most people in India do. Lugging means driving at a low engine rpm on a high gear. Most people are taught that shifting up to a higher gear as early as possible results in better fuel economy. So keeping that in mind, people refuse to shift down when they are accelerating. So they are putting more load on the engine to accelerate.
Why shouldn’t you?
In a turbocharged car, when you press the accelerator hard, more boost is generated. So you are asking the car to make power at low rpms where the car cannot generate that amount of power. In a diesel car, if you press the accelerator hard, it will result in more fuel going into the combustion chamber. Now, that is a good thing for better combustion. However, since the engine rpm is low, the amount of air entering the combustion chamber is also less. This means that the engine will run very rich, something diesel cars are not meant to do. So this will result in poor fuel economy, more emissions and could also damage the exhaust system in some cases. In the case of smaller engines, lugging the engine could also cause damage to the engine.
Very easy, just downshift a gear or two and you shall have no issue what so ever.
Buy cheap fuel
Though most NA engines don’t require premium fuels, a turbocharged vehicle, especially a modified one should ideally run on the best possible fuel to get the max out of the car. This will prevent the car from knocking and will make sure you get the best performance out of your car. While we tested the Fiat Punto Abarth and the Polo GT TSi, we found that premium fuel did make the drive better.
Don’t floor the car while coming out of a turn
Why you may ask? Let’s simplify it. To make sure that the car is stable while cornering, the front and the rear slip angle need to be the same. In case there is variation, it will result in either understeer or oversteer. Slip angle changes with the accelerating, braking or hard cornering. In a turbocharged car that suffers from turbolag, there is a moment when the turbo spools up and a lot of power gets transferred to the wheels instantly. In a rear wheel drive car, you will oversteer in that case and in a front wheel drive car, you will understeer.
The best way to prevent this is to make sure you modulate the throttle while coming out of the turn instead of going full throttle.
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