How Much Horsepower Does a Turbocharger Add?

What Is an Aftermarket Turbocharger?

Before we go into depth about turbo HP increases, you need to know more about what turbochargers are and how they work when installed. An aftermarket turbocharger is a type of forced induction system – which means it compresses the air that flows into the engine to increase power and efficiency. Feeding compressed air into your engine allows it to force more air into your cylinders. More air means more fuel can be added, resulting in more power from each explosion in each cylinder — and more horsepower overall. To achieve this boost in turbocharger horsepower, an aftermarket turbocharger uses the existing exhaust flow from the engine to spin a turbine, which in turn spins an air pump. Turbines in aftermarket turbochargers can spin at speeds of up to 150,000 RPM – about 30 times faster than any stock engine could ever achieve.

Exactly How Much Horsepower Does a Turbo Add?

Now that you know what turbochargers are, we can go into more detail about the turbo HP gain you can get from adding one to your vehicle. So, how much horsepower does a turbo add after installation? As we mentioned, aftermarket turbochargers allow your engine to burn more fuel and air by packing more into the engine's cylinders. The typical turbo HP gain you'll see with most aftermarket turbochargers is six to eight pounds per square inch (PSI). Because normal atmospheric pressure is about 14.7 PSI at sea level, you're getting about 50 percent more air into the engine from adding a turbocharger. Therefore, you would expect a 50 percent increase in horsepower in a perfect scenario, but not all turbochargers are perfectly efficient. Factoring in typical inefficiencies, like the backpressure added from having a turbine in the exhaust flow, you're more than likely going to see a 30 to 40 percent turbo HP increase. This means you could use a turbocharged four-cylinder engine in place of a larger V6 engine, and a turbocharged V6 could replace an even larger V8 engine with no loss of performance.

Are Aftermarket Turbochargers Bad for Your Engine?

The draw of an aftermarket turbocharger, and the added horsepower, can be powerful when you start to picture yourself flying down an open road at full force. But any talk of turbochargers can eventually turn to the possibility of them being bad for your engine. Technically, a turbocharger is not bad for your engine. Hell, they were built to work together, and they've been doing a pretty good job since 1905 – but everything comes down to proper installation.

Improperly installed aftermarket turbocharger systems can be highly damaging to the engines on which they're mounted. Aftermarket turbochargers are rated according to the amount they deliver in PSI – remember that most turbochargers offer six to eight PSI. Stock engines on cars or trucks work efficiently with additional power and minor tuning between five to seven PSI. Levels of eight to 12 PSI often require reinforced internal components, such as a heavy-duty valve train or special pistons. Aftermarket turbochargers that function above 12 PSI often require professional-level installation and engine modification to prevent severe damage to your engine block and internal components. In short, if you're thinking about adding a turbocharger to your vehicle, you'll more than likely want to get it professionally installed to prevent any engine damage (or, you better have some serious skills and knowledge about your engine). It's also worth noting that in some cases, even properly installed and tuned aftermarket turbochargers that are negligently driven with no regard for the vehicle can also fail and permanently destroy an engine.

Can You Install a Turbocharger in Any Vehicle?

Yes, thankfully, aftermarket turbochargers are available for more than just high-performance sports cars. Still, they can be a bit tricky if you're not a seasoned veteran of the car modding world. You can buy an aftermarket turbocharger on its own, but it will be useless and harmful for your engine – especially if you're driving something like a midsize sedan. Adding a turbocharger to your ride means also installing a wastegate, an intercooler and a blow-off valve. The aftermarket turbocharger kits available at Lethal Performance come standard with these components, but that's not always the case. Because of the extreme amount of air and pressure an aftermarket turbocharger can produce, most require a wastegate on the exhaust side to help regulate all the pressure exerted to the desired PSI. In addition, a blow-off valve will help relieve some of the excess pressure created by the turbocharger – it's typically actuated once you put your foot to the throttle. Finally, you'll also need an intercooler. Using exhaust gasses to achieve all that turbocharger horsepower means generating a lot of heat. Intercoolers are used to keep the air cool, so you don't melt any plastic components under your hood when hauling some serious ass on the road. These three components are vital to giving you the horsepower you need without accidentally blowing up your engine.

Having all the skills to install these components properly is a must if you consider adding a turbocharger to a standard vehicle. We highly recommend you go to a professional if you're going to make the attempt.

The Cost of Adding a Turbocharger to Your Car

We're not going to lie. Adding a turbocharger to a naturally aspirated stock engine can be a complicated and expensive job – but one that is so worth it in the end. An aftermarket turbocharger on its own can sell anywhere from $500 to $2,000, but you'll need to factor in those other components that keep your engine protected. A complete aftermarket turbocharger kit that includes all the parts you need will likely run you anywhere from $7,000 to $10,000. And, you'll need to factor in the cost of labor if you're going to a professional installer. Sure, it's an expensive build – but can you really put a price on the freedom and fun you'll gain when you're behind the wheel of a ride that can put any other car on the road to shame? That, friends, is priceless.