Recommend a car with a twist - bit of maths required

Soldato
Joined
18 Oct 2002
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Rather than a usual spec me a car thread, I've gone for one with a difference for a bit of fun (although there is some usefulness to it for me), so I set you a maths challenge with a recommendation required at the end. Here's the parameters for a new car:

  • I currently commute 75 miles every weekday and will do so for the next three years
  • I pay £1.07 for a litre of V Power, which my car requires
  • I get an average of 19mpg on my commute which, although predominately on the motorway, is quite stop start. My car ranges anything between 10mpg and 22mpg on a decent length journey depending on whether it is urban or steady motorway cruise. (I hope this gives you context as to what to use for a smaller car's fuel consumption in your workings)

So the question is, what car would you recommend that I could buy and fuel from the savings I will make in the petrol alone for the next three years on my current car. For the purposes of the exercise assume zero servicing, maintenance, insurance and fueling costs. i.e. only consider purchase price today and fuel costs for three years.
 
Almost anything with a 2 litre engine or below and no turbo should see some good savings.

75 miles per day is 20k per year, so you might want to consider one of those nasty oil burning things :D
 
60k miles at 107.9 @ 19mpg would be £17167.84

60k miles at 98.9 for diesel @ 40mpg would be £6743.99

£10k saving over 3 years (ignoring car cost difference, insurance, tax etc)

Although somehow i think ive screwed it up
 
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60k miles at 107.9 @ 19mph would be £17167.84

60k miles at 98.9 for diesel @ 40mpg would be £6743.99

£10k saving over 3 years (ignoring car cost difference, insurance, tax etc)

Although somehow i think ive screwed it up

I like your wokrings. So what 10K diesel are you going to recommend me for my commute?
 
Very clever. What's the range of a Gwhizz? I can't power it up at work so it will need to do 75 miles.

Barely half that.

And I assume you can buy one for less than the cost of 3000 gallons of fuel?

It's about £7k IIRC, so cheaper than the fuel. However you'd need your head examined to even consider commuting that sort of distance in such a piece of crap. I do ~60 miles a day, and I had 1.1 Mk2 Fiesta for a year. Was quite fun at first, but the novelty wore off in about 3 minutes.

You want something comfortable with a decent bit of power, Mondeo TDCi, Beemer 3 series etc.
 
[TW]Fox;10208289 said:
For £10k? and 30mpg average cuts the saving in half doesnt it? So £5k? Meaning he cant buy it for the saving in fuel.

Doesnt fit with his mathematics, but it would avoid the feeling of downgrade yet still save him money
 
It was a tongue in cheek suggestion for someone who currently has a gorgeous car and will be facing a huge downgrade to anything available for £10k and which does 40mpg. He needs to consider whether the huge downgrade would be worth it, or whether a compromise would be better.
 
Current car a CL500.

However one point to note here is that I'm not getting rid of the merc. I was interested in seeing if it is really viable to have a second car just for the commute and not really spend any more than if I did 60,000 miles in the CL.

Although clearly the economics of it all are not quite as simple as I have made in my request, I find it interesting that a half decent 320d of C220CDi can be bought on the fuel savings alone.

To change the original request a little, lets say half the 10K fuel savings will be needed to run/insure/tax the car for three years. That leaves 5K as a very realistic budget for buying a car now and it not costing me any more than just driving the CL. Is there anyway I can get a 5K diesel and not think I've gone to automotive hell given what I'm used to driving?
 
60k miles at 107.9 @ 19mpg would be £17167.84

60k miles at 98.9 for diesel @ 40mpg would be £6743.99

£10k saving over 3 years (ignoring car cost difference, insurance, tax etc)

Although somehow i think ive screwed it up

I get a smaller figure for the first calculation but dead on for the second. I worked them out as follows if anybody wants to confirm that I'm doing the calculations properly:

Current Car
60000 (Miles) / 19 (MPG) = 3157.894737 (Gallons Used)
3157.894737 x 4.546 = 14355.78947 (Litres Used)
14355.78947 x 1.079 (£ per litre) = £15489.90

Potential Diesel Car
60000 (Miles) / 40 (MPG) = 1500 (Gallons Used)
1500 x 4.546 = 6819 (Litres Used)
6819 x 0.989 (£ per litre) = £6743.99

Total Savings
15489.90 - 6743.99 = £8745.91
 
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I get a smaller figure for the first calculation but dead on for the second. I worked them out as follows if anybody wants to confirm that I'm doing the calculations properly:

Current Car
60000 (Miles) / 19 (MPG) = 3157.894737 (Gallons Used)
3157.894737 x 4.546 = 14355.78947 (Litres Used)
14355.78947 x 1.079 (£ per litre) = £15489.90

Potential Diesel Car
60000 (Miles) / 40 (MPG) = 1500 (Gallons Used)
1500 x 4.546 = 6819 (Litres Used)
6819 x 0.989 (£ per litre) = £6743.99

Total Savings
15489.90 - 6743.99 = £8745.91

No your right i knew something was wrong but didnt click, dont know what the hell i did
 
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