Turbochargers over Superchargers
Turbochargers and superchargers are two distinct technologies designed to increase the power output of an internal combustion engine. While both serve the same fundamental purpose, they operate in fundamentally different ways, and turbochargers are often regarded as more efficient for several compelling reasons.
1. Operational Differences:
Turbochargers: Turbochargers are exhaust-driven devices. They harness the energy of exhaust gases exiting the engine to spin a turbine. This turbine, in turn, is connected to a compressor on the intake side, which forces additional air into the engine’s combustion chambers. The extra air allows for more fuel to be burned, resulting in increased power.
Superchargers: Superchargers, in contrast, are mechanically driven by a belt connected to the engine’s crankshaft. As the engine spins, the supercharger’s compressor also rotates, compressing the incoming air before it enters the engine. This mechanical connection consumes some of the engine’s power to operate the supercharger.
2. Energy Recovery:
Turbochargers: Turbochargers have a distinct efficiency advantage because they recover energy that would otherwise be wasted. Hot exhaust gases spin the turbine, boosting power without using mechanical power from the engine. This energy recovery is a key reason why turbos are often considered more efficient.
Superchargers: Superchargers, due to their mechanical nature, consume some of the engine’s power to drive the compressor. This is known as parasitic loss and reduces the overall efficiency of the engine.
3. Fuel Efficiency:
Turbochargers: By allowing smaller engines to produce power levels comparable to larger, naturally aspirated engines, turbochargers improve fuel efficiency. The increased air density from turbocharging promotes better combustion, resulting in improved fuel economy.
Superchargers: Superchargers increase power, but they also increase fuel consumption because they use energy directly from the engine.
4. Power Loss:
Turbochargers: Turbochargers impose minimal to no parasitic load on the engine, meaning they don’t divert engine power to operate. Therefore, more of the engine’s power is available for propulsion.
Superchargers: Superchargers are connected to the engine and use some of its power to operate the compressor. This reduces the power available for driving the vehicle.
5. Altitude Performance:
Turbochargers: Turbochargers maintain their efficiency at higher altitudes where the air is thinner. This is because they are driven by exhaust gases and are not dependent on atmospheric pressure.
Superchargers: Superchargers, which rely on mechanical operation, may experience a significant drop in power at high altitudes due to reduced air density.
6. Heat Generation:
Turbochargers: While turbochargers do generate some heat, it is relatively minimal compared to superchargers. This is because they utilize the heat from exhaust gases, which are already hot.
Superchargers: Superchargers produce heat as a byproduct of their mechanical operation. This heat can be detrimental to engine performance, potentially causing overheating or necessitating additional cooling systems.
In summary, while both turbochargers and superchargers serve the purpose of increasing engine power, turbochargers are often favored for their efficiency advantages. Turbochargers are known for being highly efficient because they recover energy, improve fuel efficiency, reduce power loss, perform well at high altitudes, and generate less heat. However, the choice between the two depends on specific application requirements and performance goals.
Listed below are historical vehicles known to have used either a turbocharger or a supercharger:
Porsche 911 Turbo (930) – 1975: The Porsche 911 Turbo, often referred to as the 930, was one of the earliest production sports cars to feature a turbocharger. This rear-engine sports car became famous for its distinctive “whale tail” spoiler and its powerful turbocharged flat-six engine.
Buick GNX (1987): The Buick Grand National GNX was a high-performance version of the Buick Regal that featured a turbocharged V6 engine. In 1987, it was one of the fastest production cars in the United States, and it gained a reputation as a muscle car with a turbo twist.
Saab 99 Turbo (1978): Saab introduced the 99 Turbo, which was one of the first mass-produced passenger cars to feature a turbocharger. This compact car combined practicality with turbocharged performance, helping Saab establish itself as a manufacturer of innovative, turbocharged vehicles.
Audi Quattro (1980): The Audi Quattro was a pioneering rally car that featured all-wheel drive and a turbocharged five-cylinder engine. It revolutionized rally racing and helped popularize both all-wheel drive and turbocharging in production cars.
Ford Thunderbird Turbo Coupe (1983): The Ford Thunderbird Turbo Coupe was a performance-oriented version of the Thunderbird featuring a turbocharged four-cylinder engine. It was part of Ford’s effort to combine efficiency with performance during the 1980s.
Mercedes-Benz 540K (1936-1940): The Mercedes-Benz 540K was a luxurious and powerful car of its time. The “K” in its name stood for Kompressor, which is German for supercharger. The supercharged 5.4-liter inline-eight engine allowed this car to reach impressive speeds for its era.
Auburn 852/856 (1935-1936): The Auburn 852 and 856 were American luxury cars with supercharged engines. These cars, known for their distinctive styling and powerful supercharged eight-cylinder engines, were highly sought after during the Great Depression.
Jaguar XK120 (1948-1954): The Jaguar XK120 was one of the first sports cars to feature a supercharger as an option. The XK120 S, also called the supercharged version, had more power and could reach a top speed of over 130 mph. It was one of the fastest cars back then.
Studebaker Golden Hawk (1956-1958): The Studebaker Golden Hawk was a performance-oriented coupe that featured a supercharged V8 engine. It was one of the most powerful American cars of its era, boasting impressive horsepower and torque figures.
Bentley 4½ Litre Blower (1927-1931): The Bentley 4½ Litre Blower is a legendary racing car that used a supercharger to boost performance. It was driven by famous racers like Sir Henry “Tim” Birkin and competed at prestigious events like the 24 Hours of Le Mans.