The new flagship of the next 1-series range will use a 2.0-litre, four-cylinder engine with 302bhp, BMW has confirmed.
We’ve known for some time that the current (and lovely) six-cylinder engine was going to be axed at the end of the current F20/F21 generation car, owing to the switch to a Mini chassis with transverse engines. The i6 simply won’t fit. Now we have confirmation of what will replace it when the all-new 1er arrives.
BMW says the four-pot in question, which will power the M135i, is a newly-developed lump based on an existing 2.0-litre turbocharged block. A reinforced crank and con-rods, a larger turbo and new injector valves have helped boost power to a healthy – and class-competitive – level. It’s the most powerful four-cylinder engine in the BMW Group today.
Importantly, the new M135i will be around 30bhp short of the outgoing M140i’s six-cylinder turbo engine. It’s just speculation, but it seems there’s room for a four-pot M140i at a later stage, if demand is there.
It’s understood at this stage that the M135i will come with xDrive four-wheel drive only and be capable in theory of averaging up to 41.5mpg on its smallest available wheels.
To counter the switch in handling dynamics from rear-wheel drive to front, BMW is introducing electronic dynamic aids as standard. A clever new slip-limiting tech derived from the i3 is integrated into the main ECU manages traction at the front axle and, says BMW, “significantly reduces” power understeer without bothering the stability control.
Brake-based torque vectoring is also standard and will drag the brake on the inside front wheel to tighten a line if needed. The chassis itself should be very stiff thanks to the deliberate and targeted placement of additional struts, including something called a ‘boomerang strut’ at the rear end.
Elsewhere the front-wheel drive 1er will have more rear legroom, more rear headroom and 20 litres more boot space (at 380 litres), all thanks to the switch to the upgraded Mini platform. A launch date for the new car will surely follow soon.