True MPG: most efficient coupes, convertibles and sports cars 2019

What Car?'s True MPG tests show what fuel economy you can really expect from a car. Here, we reveal the best and worst-performing coupés, convertibles and sports cars we've tested...

21 March 2019
True MPG: Best and worst coupes, convertibles and sports cars

The miles per gallon (MPG) figures published in sales brochures can tempt you into buying a particular car, but those results are often misleading. Fortunately, What Car?'s True MPG tests reveal what sort of fuel economy you can expect in the real world.

To ensure accuracy and repeatability, we use strictly controlled laboratory conditions, but the tests are based on a real-world route that takes in town, rural and motorway driving.

The results reflect what's achievable if you’re driving gently and sticking to speed limits but aren’t resorting to any unrealistically slow acceleration or special 'hypermiling' techniques.

Here we reveal the 10 most efficient coupésconvertibles and sports cars we've tested so far – plus the one that used the most fuel.


The 10 most fuel efficient coupés, convertibles and sports cars cars

10. BMW M2

BMW M2 vs Jaguar F-type vs Porsche 718 Cayman S

True MPG 31.4mpg

The M2 is effectively a steroid-enhanced version of the BMW 2 Series. Under its bonnet lies a turbocharged 3.0-litre engine that pumps out 365bhp – enough for a 0-62mph time of 4.4sec with the standard six-speed manual gearbox. Yet you can still get 31.4mpg out of the car when you drive it more gently.

2016 Porsche 718 Cayman S review

True MPG 34.4mpg

Both this entry-level version of the Cayman and the more powerful Cayman S swapped their flat six engines for turbocharged four-cylinder units back in 2016 in order to reduce fuel consumption and emissions. The downside is that they no longer sound as special as they did.

Read our full Porsche 718 Cayman review or see what discounts are available


8. BMW 43oi Convertible

Audi A5 Cabriolet vs BMW 4 Series Convertible

True MPG 34.9mpg

Fractionally more efficient than the Cayman is the BMW 430i Convertible, despite it being a four-seater with a folding metal roof, so considerably heavier.

Read our full BMW 4 Series Convertible review or see what discounts are available


Next: the top 10 continued >

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