The need to accommodate two conventional front-hinged rear doors and sufficient rear seat leg room is said to be behind the decision to give the new car a wheelbase that's halfway between the 2690mm span of the 2 Series Coupé and the 2810mm of the 3 Series saloon.
Inside, the 2 Series Gran Coupé will sport a new interior layout that's also set to be adopted by the successors to today’s 2 Series Coupé and 2 Series Convertible, which are due in 2020.
The turbocharged three-cylinder and four-cylinder engines of the 2 Series Gran Coupé will mirror those of the existing line-up.
On the petrol side of the range, expect a 134bhp 1.5-litre three-cylinder engine in the 218i, 181bhp and 242bhp 2.0-litre four-cylinder units in the 220i and 225i, with a more potent version in the M235i. Among the diesels will be 148bhp, 187bhp and 221bhp 2.0-litre four-cylinder engines in the 218d, 220d and 225d respectively.
Like its two-door siblings, the 2 Series Gran Coupé will offer a choice of a standard six-speed manual or optional eight-speed torque-converter automatic gearbox, with xDrive four-wheel drive available as an option. However, the latter will be offered in combination with only a limited range of engines.
The highlight of the new line-up, though, will be the M2 Gran Coupé.
This model will use the same 365bhp turbocharged 3.0-litre in-line six-cylinder engine as its highly lauded two-door sibling. It will be offered with a six-speed manual or a seven-speed dual-clutch automatic gearbox.
Although it's still early days, that engine – designated S55B30 - is expected to provide the M2 Gran Coupé with similar performance to the M2, which has an official 0-62mph time of 4.4sec in manual form and an electronically limited top speed of 155mph.
The 2 Series Gran Coupé will be produced alongside the 2 Series Coupé and 2 Series Convertible at BMW's plant in Leipzig, Germany.
A plug-in hybrid model is also mooted. This is expected to use BMW’s turbocharged 1.5-litre three-cylinder petrol engine and an electric motor mounted within the forward section of a standard eight-speed automatic gearbox.
With a lithium ion battery pack positioned beneath the floor of the boot, the hybrid set-up is intended to provide the 225e with an electric-only driving range of up to 31 miles.
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