It's no longer relevant to lament the fact that "coupe" no longer means "two-door." Automakers will win the battle of stupid names through pure attrition. Give it six doors, a hatch, and no roof and call it a coupe if you want. We give up. You win.
As a sedan version of the 6 Series Coupe it should fit into the space between the 5 Series and the 7 Series, numerically.
The reality is more sketchy.
It's based on the larger 7 Series but is two inches lower and four inches longer than BMW's flagship sedan, while also being four inches longer than the 6 Series Not Gran Coupe. It's also 13 inches longer than Blake Griffin wearing four-inch heels. Think about it.
A 650i Gran Coupe's power comes from a twin-turbo 4.4-liter V8 producing 445 horsepower and 480 lb-ft of torque, which is enough to propel it to 60 mph in 4.8 seconds. A little further down is the TwinPower turbo six-cylinder 640i, which comes with a respectable 315 horsepower and 330 lb-ft of twist. All engines are tied to a flappy-paddle 8-speed automatic.
In person, the 6 Series Gran Coupe hardly resembles its actual Coupe sibling aft of the nose. It looks more like a 5 Series that had a 5 Series GT sit on it. Or maybe a 3 Series that was pulled between two X6 Ms.
But in a good way.