“Yaar, a friend of mine has bought the latest Vitz. What acceleration man, mind-blowing.”
I can’t even remember how many times I heard a similar sentence back in the days when I would speed up my car thinking that even Vin Diesel could not beat me if he was in a similar vehicle. Unfortunately, I would never be able to know, but one thing I did know was that some cars were more powerful (and faster) than others. How would I know which one was faster? Easy, get the size of its engine and off you go; the bigger the engine, the more the power. This formula actually worked very well for me, until the day I took a one-way flight to England. Thankfully I got my UK driving license within four months and got a chance to drive my uncle’s new BMW. How fast was it? Well, not too fast since it had a 2000cc diesel engine just like Corolla 2.0D. At least that is what I told myself until I hit the throttle and my God the car was fast. But, how on earth was it faster, surely it was just a “2.0D” like our local “2D Corolla”. Then why did it accelerate so brutally?!
RELATED: Horsepower vs Torque – What is the difference?
My curiosity took me through a lot of research, and by the end of it, I realized that my formula for knowing which car is faster was utterly wrong. Comparing vehicles by measuring their engine size was like comparing the strength of men using their weight. A bodybuilder/powerlifter might weight less than an overweight gentleman but is likely to come out stronger in most cases. Similarly, a car can have a smaller engine, yet can be much faster than its rival – see McLaren MP4-12C with a 3.8-liter engine vs. Ford Mustang 5.0-liter engine. McLaren will wipe the floor with a Ford.
Engine Output
Since car engines are becoming increasingly sophisticated by the day, it would be tedious to compare their sizes and keep track of the technologies within them. To get around this, experts use the metric “Maximum Output” to compare the power of car engines.
The maximum output of an engine is measured using a device called dynamometer which calculates the force of an engine at different RPMs. The maximum output measured is then listed down in the car’s brochure along with the RPM reading on which it was obtained. The line below shows the maximum output of a Toyota Yaris (Vitz) shown in its UK brochure.
Maximum Output (kW@rpm): 51/6000
Using this information we know that the maximum output of a 1000cc (1.0-liter) Toyota Yaris (Vitz) is 51 kW when the engine touches 6000 RPM.
Engine Output and Horsepower
Just like the world cannot agree on whether to use miles or kilometers we have a similar problem with maximum output. The most popular units to measure an engine’s maximum output are:
- bhp (brake horsepower or often called just horsepower)
- kW (kilowatt)
- PS (pferdestärke)
We can easily convert an engine’s bhp to kW or PS using the following formulas:
- 1 PS = 0.986 horsepower
- 1kW = 1.341 horsepower
Using this we can calculate the maximum output of a 1000 cc (1.0 liter) Toyota Yaris (Vitz) as being 68.4 horsepower.
Comparing Horsepower
To put this concept into perspective, I decided to apply it to cars that I had driven in Pakistan over the years and see if my impressions about them hold true with the numbers or not.
| Car | Variant | Engine | Maximum Output |
| Toyota Corolla (2003) | GLi | Petrol 1300 cc | 87 bhp* |
| Toyota Corolla (2005) | SE Saloon | Petrol 1600 cc | 110 bhp* |
| Toyota Vitz (2006) | – | Petrol 1000 cc | 68 bhp |
| Toyota Corolla (2015) | Altis | Petrol 1800 cc | 138 bhp |
*These values have been verified online but the source was not as authentic as the manufacturer itself
The values obtained do match somewhat with what I experienced such as Toyota Corolla GLi which has a 1300cc petrol engine would struggle to climb the road leading to Pir Sohawa (Islamabad) on 2nd gear with five people unless I had a high approaching speed. I have found my old automatic Toyota Vitz (1000cc petrol engine) to be found wanting for more as well.
Toyota Corolla SE Saloon (1600 cc petrol) and Toyota Altis (1800 cc petrol) however seem to cruise through those hills which appears to tally with their official horsepower figures.
Power to Weight Ratio
This analysis seems reasonable, but there is one caveat. A 1300cc engine with 87 bhp might feel powerful on a car the size of a Suzuki Mehran but would lack the punch when fitted on a vehicle the size of a Toyota Land Cruiser.
To find the real power of a car, we would need to consider its horsepower and weight, bringing us to the concept of power to weight ratio. As its name suggests the power to weight ratio is calculated by taking a car’s horsepower and dividing it by the car’s curb weight** in tonnes.
** Curb weight of a car is defined as its weight without any baggage or passengers in it
Using this formula we get the following results when comparing the same cars as above.
| Car | Variant | Engine | Maximum Output | Curb Weight | Power to Weight Ratio |
| Toyota Corolla (2003) | GLi | Petrol 1300 cc | 87 bhp* | 1160 kg* | 75 |
| Toyota Corolla (2005) | SE Saloon | Petrol 1600 cc | 110 bhp* | 1160 kg* | 95 |
| Toyota Vitz (2006) | – | Petrol 1000 cc | 68 bhp | 980 kg* | 69 |
| Toyota Corolla (2015) | Altis | Petrol 1800 cc | 138 bhp | 1275 kg* | 108 |
*These values have been verified online but the source was not as authentic as the manufacturer itself
Since the overall results have not changed much, it would mean that my personal impressions about the power of each car was on par with the actual numbers.
Using this formula, I decided to pool some of the cars available in Pakistani market together and see how they stack up against one another.
| Car | Variant | Engine | Max. Output | Curb Weight | Power to Weight Ratio |
| Saloons | |||||
| Honda Civic (2018) | VT. Turbo | Petrol 1500 cc | 170 bhp | 1282 kg | 133 |
| Honda Civic (2018) | i-VTEC | Petrol 1800 cc | 138 bhp | 1267 kg | 109 |
| Toyota Corolla (2018) | 1.8L Altis | Petrol 1800 cc | 138 bhp | 1275 kg* | 108* |
| Honda City (2018) | City 1.5L | Petrol 1500 cc | 118 bhp | 1155 kg* | 102* |
| Toyota Corolla (2018) | 1.6L Altis | Petrol 1600 cc | 120 bhp | 1275 kg* | 94* |
| Toyota Prius (2018) | Hybrid 1800 cc | 121 bhp* | 1395 kg | 87* | |
| Honda City (2018) | City 1.3L | Petrol 1300 cc | 98 bhp | 1155 kg* | 85* |
| Toyota Corolla (2018) | XLi | Petrol 1300 cc | 84 bhp | 1275 kg* | 66* |
| Hatchbacks | |||||
| Honda Fit (2015) | Hybrid 1500 cc | 130 bhp | 1140 kg* | 114* | |
| Toyota Aqua (2014) | Hybrid 1500 cc | 99 bhp | 1132 kg | 87 | |
| Suzuki Swift (2018) | DLX | Petrol 1300 cc | 90 bhp | 1050 kg* | 86* |
| Mitsubishi Mirage (2015) | Petrol 1000 cc | 70 bhp * | 845 kg* | 83* | |
| Suzuki WagonR (2018) | Petrol 1000 cc | 67 bhp | 830 kg | 81 | |
| Suzuki Cultus (2018) | Petrol 1000 cc | 67 bhp* | 835 kg* | 80* | |
| Toyota Passo (2014) | Petrol 1000 cc | 68 bhp* | 910 kg* | 75* | |
| Suzuki Mehran (2018) | VX | Petrol 800 cc | 39 bhp | 630 kg* | 62* |
*These values have been verified online but the source was not as authentic as the manufacturer itself
Since I have not personally driven most of these cars, I cannot endorse the numbers, but as they say, the numbers do not lie. From what we can see, Honda Civic i-VTEC Turbo is surprisingly powerful and easily defeats all other cars in its segment hands down. If that was not enough Honda gave another pounding to its competitors in the hatchback segment with the help of Honda Fit beating the next best, Toyota Aqua, by a comfortable 27 bhp/tonne. Putting Honda Fit aside though, the table shows us that our very own Suzuki Swift competes quite well with its imported rivals but has a long way to go if it wants to give any serious competition to the chart topper in this particular table.
Do you think these numbers match your personal experiences? Please do let us know in the comments section below.
