Read the full story of BMW's next 3-series
In its design and packaging, the UKL is a vastly different proposition from the second-generation rear-drive 1-series that will make its world debut at the Geneva motor show in March. The primary difference between the two is that the front-drive car has its engine mounted transversely under a comparatively short bonnet rather than longitudinally under a typically long bonnet.
With drive being sent to the front wheels rather than channelled via a propshaft to the rear wheels, the layout has given BMW’s designers the freedom to dispense with the transmission tunnel running back through the interior. This should increase the amount of available space, especially in the rear.
The new layout has also allowed BMW to rethink the car’s proportions, with the front bulkhead and A-pillars being brought further forward. This will increase the volume of the cabin to a level comparable with Europe’s best-seller, the Volkswagen Golf, and the Audi A3.
Full story: BMW 1-series owners 'think their car is FWD'
The UKL will also gain a more upright windscreen and larger door apertures. Insiders talk of the five-door hatchback adopting a silhouette similar to that of the 5-series GT, albeit on a smaller scale.
As well as the adoption of front-wheel drive and the packaging improvements it brings, the new entry-level model will offer buyers the choice of frugal turbocharged three-cylinder engines along with a new generation of turbocharged four-cylinder units — all part of BMW’s EfficientDynamics programme.
The new three-cylinder petrol and diesel engines, known under the codenames N37 and N38, are set to be 1.5 litres in size. They have been designed in a modular nature and will share components with the BMW’s traditional 3.0-litre, six-cylinder petrol and diesel engines.
Read more on BMW's new three-cylinder engines
Ranged above the compact three-cylinder engines will be new 2.0-litre, four-cylinder petrol and diesel units. The new engines also reflect BMW’s 500cc-per-cylinder engineering philosophy. Both will run the latest in turbo and piezo-valve-equipped injection technology.
As with the smaller motors, the four-cylinder units are planned to run in combination with EfficientDynamics tech that will include stop-start, brake energy recuperation and a new heat recovery system that uses waste heat from the exhaust to generate electricity to power the car’s ancillaries.
Unlike its rear-wheel-drive 1-series sibling, the UKL is not scheduled to run BMW’s six-cylinder motors, which are designed exclusively for a longitudinal layout. But that’s not to say that it won’t be without a performance variant. Munich insiders have revealed to Autocar plans for a resurrection of the ‘ti’ name on a Golf GTI-challenging performance model running a 220bhp version of BMW’s new turbocharged 2.0-litre engine.
This new model will be used to support a successor to BMW’s upcoming 1-series M Coupé, which is tentatively due to appear in 2013.
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