BMW M135i Automatic Three-Door review

by David Finlay (4 October 2012)

One of BMW's more recent wheezes has been to create a new category of cars known as the M Performance models. These are more serious and purposeful than those badged M Sport, a largely though not entirely style-driven trim level, but not quite so focussed as the fabled M models of which the M3 we tested recently is an excellent example.

The new M135i is an M Performance car, though to take a look at the figures you might not immediately guess it. Into the 1-Series hatchback BMW has fitted its 320bhp three-litre twin turbo petrol engine (making this the most powerful production 1-Series after 335bhp 1M Coupé), and you can imagine the drama that has resulted.

Actually, to some extent you don't even have to imagine it. Right there on paper it says that the M135i will accelerate from 0-62mph in 4.9 seconds (if fitted with the automatic transmission which we'll be discussing shortly), and although the official top speed is 155mph it's clear from the enormous amount of power with which this small car is blessed that it would go quite a bit quicker than that if the electronics allowed it to.

Quoting figures is, however, no way of conveying the excitement that the M135i can generate. On full throttle it is, for a hot hatch, brutally fast - no rival shows anything like the same determination to hurl itself over the horizon. And it sounds simply wonderful. Turbocharged four-cylinder engines can often sound a lot tamer than they really are, but the six-cylinder BMW unit produces a quite soul-stirring howl.

The fact that the test car had an automatic gearbox should not be seen as a disappointment. This one has eight gears, and that's enough to overcome the inefficiency inherent in all conventional automatics by ensuring that the engine is always operating as close as possible to the ideal revs for any given situation, whether that be performance or fuel economy.

The M135i auto is therefore slightly quicker in a straight line than the six-speed manual, which has a 0-62mph time of 5.1 seconds, while also performing better in terms of official fuel economy (37.7mpg rather than 35.3mpg) and CO2 emissions (175g/km, not 188g/km). Of course you'll go through fuel at a much quicker rate if you use the power, but aren't those extraordinary "green" statistics for a car with 320bhp?

But despite all the frolics, it's very obvious that this isn't a "real" BMW M car. For a start, and despite 18" wheels not available elsewhere in the 1-Series range, it looks very ordinary. If you parked it beside a last-generation Ford Focus RS most people would barely notice it was there, and hardly anyone would guess that it was the more powerful of the two.

Characteristically for a BMW, it also looks quite ordinary on the inside. And even with £515 worth of adaptive M Sport suspension, as fitted to the test car, it's not that exhilarating to drive. It's competent, certainly, but in performance terms it's a bit of a straightline special, not really prepared to deal with all the power the engine can provide unless it's pointing directly fowards on a well-surfaced and preferably dry road. Tight corners have to be treated with caution, either by you or, if you're being careless, by the traction control.

Apart from that, there's very little drama, very little sense that this is a sporty machine. It doesn't feel particularly sharp, more like a relaxed and refined 1-Series with, when required, sensational overtaking ability and a wonderful soundtrack. And while there will certainly be people who find that satisfying, there will be others who would have preferred something that, like the true M cars, provides a sense of occasion every time you climb aboard.

Fascinating car, though, and at £31,595, including £1600 for the automatic transmission, a surprisingly inexpensive one considering how much BMW has charged for hopelessly inferior performance-oriented 1-Series models in the past - specifically this one.

Then again, be prepared to pay much more if you want your home comforts. The test car was fulsomely equipped with optional extras, none of which (other than the adaptive suspension) contributed to its hot hatchery, and if you wanted to buy one just like it you'd have to hand over £37,900.

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