The arrival of a new BMW M car is always big news – and the racy, range-topping M135i is no exception. Following in the wheeltracks of the legendary E30 M3 and last year’s limited-edition 1M Coupe, the newcomer certainly has a lot to live up to. And on paper, the M135i has all the right ingredients to succeed.
Under the bonnet is a muscular 316bhp Twin Power 3.0-litre straight-six, which is mated to either a six-speed manual box or a slick eight-speed automatic. Elsewhere, you’ll find an uprated chassis, variable-ratio sports steering and more powerful brakes.
Yet despite this significant mechanical makeover, BMW’s designers have done very little with the car’s styling. In fact, at a glance the M135i could easily be mistaken for an entry-level 116d. A subtle bodykit, twin-exit exhausts, blue brake calipers and silver-finish mirrors are the only real clues to its potential. It certainly has none of the wild-looking Subaru’s aggressive, head-turning appeal.
The low-key theme continues inside. There’s a smattering of M logos, revised dials and heavily bolstered front sports seats, but otherwise the M135i feels like any other model in the 1 Series line-up. That means you get the same high-quality fit and finish, logically laid-out dashboard and a perfect, low-slung driving position. And while the BMW isn’t quite as well equipped as the Subaru, all the essentials are covered, including leather trim, Bluetooth and climate control.
There’s also little to separate the M135i and its rival in terms of practicality. A three-door layout hampers access to the rear of the 1 Series, but once inside passengers get decent head and legroom. Better still, a more versatile five-door version is available for an extra £530. The well shaped 360-litre boot is 60 litres down on the Subaru’s, but a hatchback opening and maximum capacity of 1,200 litres with the seats folded allows the BMW to claw back some practicality points.
Yet any thoughts of family friendly credentials vanish the moment you prod the starter button. At the track, the M135i put on a crushing display, beating the Subaru in all of our acceleration tests. The combination of a responsive eight-speed automatic box and muscular 450Nm torque output meant the 1 Series took only 4.8 seconds to complete the benchmark sprint from 0-60mph, and just 7.5 seconds to blast from 50-70mph in eighth gear – that’s a full 2.6 seconds quicker than the Subaru could manage in sixth.
In the real world, the M135i feels even faster. With peak torque arriving at only 1,250rpm, the BMW responds instantly to the throttle, allowing you to breeze past slower cars. Better still, the brilliant gearbox delivers crisp shifts via the steering wheel paddles or smooth auto changes, while the engine emits a hard-edged mechanical growl when extended.
The BMW continues to excel when the road gets tight and twisty. Precise and well weighted steering, strong grip and beautifully balanced rear-wheel-drive handling make the 1 Series an agile and entertaining companion, while the uprated brakes are powerful and progressive. As with other models in the line-up, drivers can switch between EcoPro, Comfort, Sport and Sport+ settings, which alter the throttle sensitivity and steering weighting to suit the road conditions and your mood.
Yet despite its hi-tech electronic rear diff, the M135i can’t match the all-weather traction of the four-wheel-drive Subaru, and only brave drivers will turn off the 1 Series’ traction control in anything other than bone-dry conditions.
It’s also worth noting that our BMW test car was fitted with the optional M Sport Adaptive sport suspension, which delivers firmer damping and stronger body control in Sport setting, and a remarkably supple ride in Comfort mode. The set-up costs an extra £515, but it’s worth every penny. Even with the suspension at its firmest setting, the BMW is more relaxing over long distances thanks to much lower levels of wind, road and engine noise.
At £31,595, the M135i costs more than the Subaru – although if you opt for the six-speed manual box, the price drops by £1,600. A pre-paid servicing pack, lower emissions and slightly better fuel economy allow it to claw back some ground in the financial stakes. Factor in stunning performance and engaging driving dynamics, and the 1 Series looks like a strong contender for victory.