What do petrolheads mean by “performance” of a car?

By MUNGAI KIHANYA

The Sunday Nation

Nairobi,

24 June 2018

When motoring enthusiasts – so-called “petrolheads” – talk about the performance of a car, exactly what do they mean? Is it the top speed or the acceleration, or the fuel economy, or the rated power, or the stability, or what?

Although it can be exciting, the top speed of a car is not very useful. The reason is that you can hardly ever reach it legally. Governments all over the world have put up limits on all roads.

In Kenya, the highest you can drive is 110km/h and this is only allowed on dual carriage highways. I think there are only two such roads in the entire country: the A2 between Nairobi and Kenol (popularly known as Superhighway) and the A104 between Nairobi and Limuru (Waiyaki Way).

So, if your car can do 300km/h, you can’t enjoy that “performance” on any of our roads. Furthermore, even if the law didn’t prohibit it, you still can’t clock that top speed because there are so many obstacles on the typical road – bumps, corners, other slower vehicles etc.

Acceleration is probably a better indicator of performance. This is how quickly the car gains speed. It is normally stated as the time to accelerate from zero to 100km/h. The typical family saloon takes about 10 seconds when driven aggressively on a clear level road. Race cars can do so in less than three seconds.

Again, because of obstacles along a normal road, most drivers need several minutes to rich 100km/h.

The most ignored, yet, in my view, most important, performance indicator of a car is the fuel economy. Indeed, the situation is so bad that motorists generally assume that a high-performance car should have high fuel consumption! But the truth is that a car that consumes less fuel is preforming better. It is more economical.

The rated power of the car’s engine is a meaningless quantity to the motorist! It tells you nothing tangible about the car: not how quickly it can accelerate; not how fast it can move; not how much load it can pull; not how much fuel it will consume; nothing! I don’t even know why manufacturers insist on quoting it. The less said about power, the better…

Stability is another ignored performance indicator. One way of assessing it is by finding out the highest speed at which the car can go around a given corner without losing balance. That is, without any of the wheels lifting off the ground.

So; which of all these factors would be the best to gauge the performance of a car? In my view it is all of them…excluding the (useless) power. Furthermore, I would give all of them equal weight for I think they are equally important.