Datasheet Statistics

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n its raw format, the Datasheet contains a lot of useful information. It is possible to ascertain a great deal of information using just the Excel sheet. But there are other ways to look at the data.

I’m a fan of statistics. There are only a few things I like better than to sit down with a nice glass of diesel and a computer, preferably using a spreadsheet, getting the poor processor to recalculate seemingly thousands upon thousands of repetitive calculations. The charts that are shown below didn’t take all that long to produce on my main machine. On my wife’s laptop Pentium 133, they were a bit slower to produce.

These two charts illustrate how the DervMan’s Performance score filters out some of the influence of both gearing and aerodynamics. The Performance measurement also attempts to filter out the effects of manufacturers deliberately tuning their cars for the 0 - 60 (or 62) mph dash. There are several examples of this, but the most notable is Citroen’s Saxo VTR being geared to make 60 in second gear, thus reducing the 0 - 60 time by around three seconds compared to the Peugeot 106 XS. The boy racer would take the Saxo - a 0 - 60 time of 9·3 seconds looks much quicker than 12·2 seconds, which is what the Peugeot manages with the same engine. Yet, the Peugeot 106 weighs slightly less (giving it better power and torque to weight ratios). Whilst the Datasheet does give the Saxo a slightly higher DervMan Performance score, of 31·4 compared to 30·7 for the Peugeot, a difference of 0·7 won’t be felt by most drivers.

This chart shows the Weight Rating compared with the DervMan Performance score for all cars in the Datasheet. This tells us several things. The first is that the greater the Weight Rating (the total of the power to weight and torque to weight figures), the greater the performance of the car. We would expect this, since the Weight Rating is part of the Performance calculation. It also illustrates that most cars have a WR between 200 and 300 with a performance score of between 20 and 40. If the Datasheet knew how many of each model and powertrain of cars there were on the roads, it would also be able to tell us the average car on the road, rather than the average car in the Datasheet.

The second chart shows the maximum speed of all cars compared with the weight ratio. It produced a slightly different plot, which again is to be expected. There are two reasons for this. One, the most obvious, is that some cars are electronically limited (usually to 155, but the MCC Smart Coupe is limited to 84 mph!). You can clearly see a line of cars with a maximum speed of 155. The second is that my Performance score attempts to filter out the influences of gearing and aerodynamics as much as possible, but the maximum speed cannot do this. Two cars with the same engine, and the same weight, will have different maximum speeds if one is much more aerodynamic than the other. Gearing can also make a difference: some cars are geared to reach their maximum speed at close to their maximum power, whereas others are overly long in the gearing department (Saabs spring to mind here, especially the low powered variants).

The Datasheet also allows us to produce some average figures. As mentioned elsewhere, because the Datasheet doesn’t know the numbers of vehicles on the road, I can’t calculate the true average. But what I can tell you is this:

The Average Car (according to the DervMan’s Datasheet v 3·7):

It’s a slightly small Family Car, a little bit smaller than a Mondeo. It has a five cylinder, 15 valve 2·1 litre engine producing 138 PS and 206 Nm, which powers the car up to 60 mph in 9·2 seconds and on to a maximum speed of 121 mph. The Combined Euromix for the car is 35·7 mpg, and it sits in Insurance Group 11. It weighs in at 1273 kg with a fuel tank capacity of 61 litres.

And I know you’re all dying to know what it is?

The nearest match is a Mk. 2 Ford Mondeo 2·0!