On our trip to Wellington, I was keeping an eye on the fuel consumption (as displayed by the on board computer) and noticed some interesting things.

For the trip to Taupo, we used 8.8 litres per 100kms. I tried quite hard to reduce the consumption with lots of careful driving and coasting down hills and gentle acceleration etc. By the time we got to the top (1054m above sea level) of the Desert Road that had increased to 9.5 l/100kms, mostly because it's all up hill with lots of speeding up and slowing down through the windy bits.

It's all downhill to Wellington so I got it back to 8.7l/100kms by the time we arrived in Taita in Lower Hutt. Thats not bad for an 18 year old 3.5l 6 cylinder engine and compares very favorably with modern Japanese engines.

I found though, that by drafting behind big trucks, I could get the fuel consumption down to 7.3 litres per 100 kms! You have to carefully pick your truck though. B Trains (scroll to the bottom) are by far the best as they are the biggest. Fuel tankers are not as good as they let too much air past down the sides of the tank. You also need to find a truck that isn't too smelly as you have to follow quite close. Stock trucks are definately a bad idea! And lastly, you need a truck that's going at a decent clip too. There is no point saving lots of fuel if the truck is only doing 80km/h as it'll take you all day to get there. So if you get into a big truck's slipstream everywhere you go, you'll easily save 20% on your fuel costs.

Credits for today's post:
Thanks to Seriocomic for letting me rip off his photo idea. Actually I didn't ask him and his is water and mine is petrol and his is better executed.

Thanks to Gabba for helping me get this shot. While I was getting this shot, the kids were growling Gabba for spilling the petrol while she tipped it. She made a damn good point though, when she said not to worry about it because it's cheaper than bottled water. Petrol is also cheaper than milk and Coke. It's good stuff

Edited: romoved some content 30/12/05