Overall rating:

These days the default option is to buy diesel in a lot of sectors - even on sports luxury coupés like the 6 Series. BMW reckons the 640d Gran Coupé will be its biggest seller, though the entry-level 640i is well worth a closer look.

Key Facts

Model driven: BMW 640i Gran Coupé
Pricing: £61,390
Engine: 3.0-litre turbocharged six-cylinder petrol
Transmission: eight-speed automatic, rear-wheel drive
Body style: four-door 'coupé'
Rivals: Audi A7 Sportback, Mercedes-Benz CLS, Porsche Panamera
CO₂ emissions: 181g/km
Combined economy: 36.2mpg
Top speed: 155mph (electronically limited)
0-62mph: 5.4 seconds
Power: 320hp at 5,800 - to 6,000rpm
Torque: 450Nm at 1,300 - to 4,500rpm

In the Metal:

There's nothing to tell the 640i and 640d Gran Coupés apart other than badging. The transition to four-door coupé from the regular 6 Series really works well, and though the width is unchanged, the Gran Coupé is a little higher to make the roofline work aesthetically with the extended wheelbase. Detail changes include bespoke chrome accents in the nose and bespoke colours.

The test cars in Sicily were all trimmed in an opinion-dividing two-tone colour scheme, mixing white and light-brown leather with Alcantara and a white wood finish. It's part of the BMW Individual collection. Colour combinations aside, the quality and sense of occasion in the Gran Coupé are notable.

Driving it:

As mentioned in the 6 Series Gran Coupé first drive (of the 640d version), the test cars were loaded with optional driving dynamics features that have a significant effect on how the car drives, so we'll reserve final judgement until we try a more standard version. Saying that, our drive did at least show that the systems could be invaluable in allowing the driver to tailor the car to his mood and the road conditions.

The 640i is powered by the most recent version of the 'TwinPower' turbocharged straight-six cylinder petrol engine that began life in the 335i a few years ago. It features a twin scroll turbocharger, direct injection and Valvetronic variable valve control. Peak power is 320hp, though it's produced in the upper reaches of the rev range so you tend to ride this engine's significant wave of torque, as its full 450Nm is produced all the way from 1,300- to 4,500rpm. Admittedly it doesn't feel quite as effortless as the 640d's engine, but in return it offers a more traditionally sporting sound when you do extend it.

As in the 640d, the eight-speed transmission is very good, smoothly shifting between the gears and speeding things up when you want it to. You're more likely to use the tactile gearshift paddles in this model too.

What you get for your Money:

The 640i Gran Coupé rides on 18-inch alloys in SE specification and comes with Dakota leather, satnav with a 10.2-inch display, parking sensors all-round, keyless ignition, dual-zone climate control, electric adjustment for the steering wheel and heated seats. The M Sport version, costing about £4,700 more, adds sharper body addenda, 19-inch alloys, black brake calipers, darkened exhaust pipes, sports seats and other detail trim changes.

Given the performance on offer, a combined economy figure of 36.2mpg for the 640i seems quite impressive.

Worth Noting

If you like the idea of a petrol-fuelled 6 Series Gran Coupé - and your wallet's a little fatter - you'd do well to hang on for the 650i version. It's powered by a new development of BMW's twin-turbocharged 4.4-litre V8 putting out 450hp and 650Nm, yet it can return 31.7mpg and emits 206g/km. It will be available with four-wheel drive as well.

Then again you could wait for the BMW M6 Gran Coupé...

Summary

Petrol power is far from dead, and though the 640d is mighty impressive, owners of the entry-level BMW 640i Gran Coupé won't feel short-changed. It looks stunning, is a real occasion inside and drives well. If your purchase doesn't take fuel costs or emissions ratings into consideration this is worth a look.