What Car?’s technicians drive new cars every week to capture our True MPG fuel economy data. Unlike official Government figures generated by a laboratory test, the numbers we publish are gained from real-world conditions.
This week we’re looking at cars that can sprint from 0-60mph in less than 6.0 seconds. The nine most efficient that we’ve tested so far include coupes, sports cars, hot hatches and grand tourers, and they shouldn’t cost a fortune to fuel – all beat 30mpg in our test.
1. BMW 640d (auto) – official 51.4mpg: True MPG 45.2mpg
The 6 Series is more grand tourer than B-road rocket, mainly due to its hefty kerbweight making it feel reluctant to change direction. However, with the 3.0-litre six-cylinder diesel upfront, it’s seriously quick – 0-60mph is dispensed with in just 5.3 seconds. It’s also got a beautifully executed cabin which is supremely comfortable – at least for those in the front – and it has lots of standard kit. For such a big car with so much performance on tap, to manage over 45mpg is quite a feat.
2. Porsche Boxster 2.7 (manual) – official 34.4mpg: True MPG 34.9mpg
The cheapest Boxster has won the Best sports car category in our Car of the Year Awards for two years on the trot. It might cost only half as much as its bigger brother, the 911, but you aren't getting only half the fun. The light, precise gearchange makes the most of the mighty engine, and the Boxster stays remarkably flat through corners and grips amazingly hard.
3. BMW M235i (manual) – official 37.2mpg: True MPG 34.8mpg
The M235i is seriously quick, and will hit 60mph from a standstill in five seconds flat. The steering is light and precise and while the chassis setup may not be as sharp as the Porsche Cayman’s, it’s still a fun car to hustle along country lanes. It has a well laid-out interior, which feels well screwed together, and has the added practicality of two rear seats and a decent-sized boot.
4. Volkswagen Scirocco 280 R (auto) – official 35.3: True MPG 34.0mpg
The Scirocco offers a blend of practicality somewhere between a hatchback and a coupe, but still cuts a dash with its sharp styling. The 280 R comes with Adaptive Chassis Control so you can tailor the ride and handling to your current mood. With 276bhp there’s enough performance to justify its position here, and the optional DSG gearbox is quick and smooth. On the negative side, the boot is small and, as with many of the cars on this list, the rear-seat space is limited.
5. BMW M135i (auto) – official 37.0mpg: True MPG 33.9mpg
While Audi’s four-wheel-drive S1 (below) could be said to be a little short on drama, the same isn’t true of this six-cylinder BMW. The rear-wheel-drive M135i is simply sensational. The ride is firm but well controlled, while the impressive performance makes for a genuine thrill-a-minute experience. What Car? Target Price suggests you can buy one for less than £28,000, making it a true performance bargain.
6. Audi S1(manual) - official 40.4mpg: True MPG 32.4mpg
For such a small car the S1 packs a serious amount of pace, both in terms of straight-line speed - courtesy of the 228bhp engine from the Golf GTI - and through the bends, thanks to its standard four-wheel-drive setup. As a result, it’s a great tool to dart along twisty country lanes, although it can feel a little anodyne at times. Despite the adjustable suspension, you’ll have to put up with a rather choppy ride, too. The cabin is well laid out and nicely finished, but the rear seats and boot are tiny.
7. BMW 435i (auto) – official 35.8mpg: True MPG 32.2mpg
The 435i is the fastest 4 Series you can buy after the M4, with a 306bhp straight-six engine that propels it from 0-62mph in 5.4 seconds. The 435i is relaxing to drive on the motorway, and exciting to drive once you’re off it, which makes it a fine grand tourer. Add plenty of space for four adults and a decent boot into the mix, and it’s easy to see why the 435i is our top coupe of 2014.
8. Porsche Cayman S (manual) – official 32.1mpg: True MPG 31.8mpg
The Cayman is one of the best-handling sports cars available at any price, as well as one of the most useable. This S model offers blistering performance, although we’d be just as happy with the entry-level car. The Cayman changes direction effortlessly and all the controls feel beautifully weighted. Compared with rivals, it’s great value, too. Overall running costs won’t be cheap, but you shouldn’t have to spend a fortune on fuel.
9. Porsche 911 Carrera S (auto) – official 34.4mpg: True MPG 31.7mpg
Considering the 911 Carerra S is a borderline supercar, with a 4.5sec 0-60mph time and a top speed of 188mph, it’s amazing to think that, driven with a little more moderation, it’ll still return north of 30mpg. That it’s still one of the best sports cars on the market today, has a beautifully executed interior, and seating – at least in principle – for four, only adds to its desirability. The downside? Well, it costs a not insubstantial £84,235 plus options, and you’ll struggle to get a discount at the dealer.
We add new models to our True MPG database every week. Visit whatcar.com/truempg to see the full range of cars we’ve tested, and find out what you really can expect to achieve on UK roads.