What Makes Cars Go Faster?by Dennis Hartman
Since the early days of the automobile, designers and car manufacturers have continued to pioneer new techniques and technologies to improve efficiency, reliability and performance. For some drivers, speed is one of the most important characteristics of a car, both in terms of acceleration in daily driving conditions and top speed for racing. There are many different ways, ranging from simple to very complex, to make a car go faster.
One of the most straightforward ways to increase a car's speed is to outfit it with a new, more powerful engine. Larger engines generally produce more horsepower by burning more fuel. For this reason, most automakers offer larger engines as options for buyers not concerned with fuel efficiency as much as speed. In addition, aftermarket car builders may install a larger engine in a vehicle to improve its speed, though at a significant additional cost.
Turbochargers and superchargers, known collectively as blowers, are another means of making a car go faster. Both of these devices force additional air into an engine's combustion chambers, resulting in a more powerful combustion and more power for driving the car with the same amount of fuel. Turbochargers mount to the car's exhaust system, while superchargers receive their power directly from the engine. To improve a car's speed, blowers are much more cost-effective than installing a new engine.
A car's tires are often a limiting factor in trying to achieve top speed. The drive wheels represent the only point where the engine's power can actually propel the car forward. Large tires with aggressive tread patterns produce more friction for faster acceleration, but also slow down the car at higher speeds. Narrower tires, which provide better turning accuracy, may result in slower acceleration.
Weight is another important part of the automotive performance equation. A lighter car will be able to travel faster than a heavier model with the same engine. Automakers continually search for new lightweight materials to use in cars, making them faster and more fuel efficient. While plastics and fiberglass have been popular materials in the past, today automakers are using aluminum alloys and carbon fiber to produce strong, light body panels and interior surfaces.
Other technologies can also improve a car's speed. One of these is electronic fuel injection, which uses a computer to control the amount of fuel the engine draws in prior to combustion. Fuel injectors replace the carburetor that was once standard in cars, giving them more power and efficiency. Aerodynamics also play an important role. Car designers test their models in wind tunnels to ensure that they will face very little wind resistance and remain firmly planted on the ground, giving the tires a firm grip on the road surface.