Forced induction isn’t a term that most of us are familiar with, but it refers to something we’ve all heard of: turbochargers and superchargers. In fact, some of us even drive one.
Forced induction has been around since the 60’s and even earlier, but it was initially exclusive to top-of-the-line sports cars, for maximum performance. Only in the past decade has it become commonly used in non-performance cars. But it’s caught on quickly; nearly every VW model sold in the past year featured a turbocharged engine, and nearly 30% of all new cars sold in 2017 were turbocharged.
The practical benefits of forced induction are pretty compelling; it makes a small engine perform like a larger one—faster and more powerfully—but with lower emissions and better gas mileage.
The mechanics of forced induction
Forced induction is achieved one of two ways: superchargers or turbochargers. Both are an external attachment to the engine, but they work very differently.
Turbochargers are comprised of a set of turbines. One turbine is spun via the flow of exhaust gases, and the other—which is connected to the exhaust powered turbine and thus derives its energy from it—compresses air to be pumped back into the combustion chamber. On a basic level, more air means more power, so turbocharged cars have more horsepower than non-turbocharged cars, all else being equal.
Turbos are incredibly efficient as they use exhaust gases that would have otherwise been emitted as waste products to generate more power. (How cool is that?)
Superchargers are also compressors that pump more air into the engine, but they’re powered by a belt that’s driven by the engine, therefore robbing the engine of power that it has already produced. For this reason, superchargers are not nearly as efficient as turbochargers, so they tend to be found mostly on high-performance cars where practicality is not the main objective.
So let’s focus on turbos (they make cooler noises anyway!) The easiest way to tell if your car is turbocharged is to do a simple google search. Just search the year, make, and model of your car, followed by the word “engine”, and you’ll see whether or not your car is turbocharged. If you see 2.0T that “T” stands for turbo.
So you found out your car is turbocharged—now what? Well, you may be surprised to hear that a turbocharged car should be treated differently from a non-turbocharged car. There are a few things you can do to take care of your turbo and minimize wear on it.
Stay out of boost
Boost is a term used to describe the charged air that is forced into the cylinders by the turbo. By staying out of it, you’re putting less stress on the turbo, and thus increasing its longevity. Boost is typically produced in more abundance in the higher RPMs, so be mindful of how hard you hit the gas, and keep RPMs low when you can.
Let the car warm up
Most drivers know to drive moderately until the engine is up to proper operating temperature. If your car has an oil temperature gauge, you’re lucky. Once the oil has reached operating temperature—usually around 205° F—it’s safe to drive however you like.
If your car has a coolant temperature gauge instead of an oil temp gauge (which is more likely), wait a few miles after the gauge is at operating temperature, because coolant warms up quicker than oil. It’s a bit of a guessing game, but it’s a good idea to play it safe and drive at least 4-5 miles before putting stress on the engine.
The reason to be sure that the oil is warmed up in a turbocharged car is because turbos spin at very high RPMs—we’re talking hundreds of thousands of revolutions per minute—and cold, viscous oil doesn’t lubricate them nearly as effectively as oil that’s warmed up a bit.
Finally, don’t shut the car off immediately after finishing your drive.
This comes as a surprise to a lot of people, as putting it in park and shutting off the car is what most of us are used to doing. But with a turbocharged car, the engine should always be left to idle for a few minutes before you switch it off. Those fast-spinning turbos generate a ton of heat, and they often become much hotter than the engine oil. This means that when the car is shut off immediately after being driving, the oil can collect in spaces in and around the turbo that are extremely hot. This in turn can cause the oil to break down while the car’s off, which shortens the oil, engine, and turbo lifespan.
Those are three fast tips to take proper care of your turbocharged engine. Following them as often as you can is a simple way to keep your engine running in top shape, minimize repair costs and maximize longevity!