While there we learnt about 'hypermiling' - a technique used to get the most fuel efficiency out of your car by driving in the most economical way, helping you beat claimed mpg figures – and easily.
Read on to find out what we learnt and how you can apply it to your own driving to get the most out of your car.
What is the MPG Marathon?
The MPG Marathon or 'miles per gallon marathon' takes place each year, dozens of new cars are entered by car manufacturers to see how their economy stacks up in real-world conditions.
Entrants are tracked over hundreds of varied miles for two full days of driving, with one aim in mind: see if the official fuel consumption figures can be beaten. And if so, by how much.
This year, we decided to take part ourselves, to see what was involved. We joined the crews on the start-line (including RAC Patrol of the Year Charlie Harding in his fully-laden patrol van) in a powerful Audi crossover estate, to find out just what’s involved in maxing your mpg on British roads.
We quickly found out that the marathon was not going to be easy - this was not just a simple driving event where you cruise around for two days and brim the tank.
Everything was regulated and watched by both RAC and independent observers. Fuel tanks were exactly brimmed and sealed at the start, and the seal would only be broken at the very end.
Real-world driving was also mandated by a tough 30mph average speed for the event. Cruising around slowly was not on – with penalties of 0.5mpg for every single minute you were over time!
The MPG Marathon, in short, is as ‘real world’ as you can make it, and sufficiently regulated to provide an excellent level playing field to discover just how economical Britain’s newest cars really are.
What did we learn?
So, what did we learn after two days, 12 hours and 445 miles of economy driving? Here are seven takeaways from MPG Marathon 2016.
1. Go with the flow
The easiest fuel-saving mindset to adopt? Simply making your car flow. Drive smoothly, gently using the steering, accelerator, brakes and other traffic to glide from point to point.
It not only feels ultra-luxurious, it’s also the most energy-efficient way of driving, and one that will deliver the best fuel economy.
2. Don’t just go slow
Some people think driving economically means driving slowly. So they’ll do 30mph on the motorway and crawl at walking pace up hills. Not only is this dangerous, it’s unlikely to be saving them much.
READ MORE: The best cars for saving on fuel
Conserving momentum and using it to your advantage is as important for setting good fuel consumption figures as simply not going very fast. You really don’t do very well if you only cut the speed.
3. Look well ahead
If you look well ahead, you’ll be able to spot that truck in the distance. You’ll see the traffic lights on red meaning you can ease back on the throttle and glide up to the obstruction usually as it clears.
By keeping your eyes focused on the distance, you can make the gentle adjustments early to ensure your flow is unimpeded. At times, when the traffic lights turn to green just as you drive up to them, your passenger will think wizardry is at work…
4. Remember the revs
The faster an engine spins, the more fuel it uses. So keep the revs low by changing up early.
You’ll soon see the fuel computer start to reward you. Just don’t let the engine labour, as you’ll quickly bog down and begin losing speed. Try to keep the engine speed in the ideal eco spot.
5. Be patient
How satisfying it is to come up behind that person who overtook you half an hour earlier?
We did just that – indeed, we’d actually forgotten the impatient sports car driver had roared past us until we came back across him later on at a busy intersection.
More haste doesn’t necessarily deliver more speed. If the roads are busy, trying to tear past everyone is unlikely to save you much time, if any.
6. Be clever with hills
Driving up hills destroys fuel economy. It may feel good to accelerate up them, but this is disastrous for your mpg.
Instead, try to drive them cleverly. If you spot a clear hill ahead, accelerate a little before you reach it, then ease off as you drive up. The extra momentum should be enough to minimise additional consumption.
7. Embrace the motorway
The most fuel-efficient roads in the country are not quiet extra-urban dual carriageways or 20mph city streets. They are motorways. This is where you can leave the car in top gear and gently cruise along, using minimal fuel.
You’re probably going faster from point-to-point than if you went cross-country, too. Shortest is not always greenest.
For more top fuel-saving advice, visit our fuel saving tips page.
The proof was in the pudding. After two days, our tank was brimmed by the RAC technicians, and the sums were crunched. Result? Average fuel economy of just over 50mpg, compared to a manufacturer-claimed average of 44.1mpg.
We’d improved our economy by around 15%, yet still set an average speed of well over 30mph. Once we’d got into it, we found driving efficiently relatively easy to do. Our best section’s mpg was on the afternoon of the second day, where the fuel computer showed more than 56mpg.
Point proven, then. With a bit of care and attention, new cars in Britain can achieve and exceed their official fuel consumption figures, even away from the confines of a laboratory. Over to you: can gentle and efficient driving see you do the same?