BMW 1 Series M135i and M6 2012 Review

BMW's M tag is far less exclusive than it once was but still signals high performance. Forty years ago in Munich BMW decided to step up its commitment to motorsport and create a specialist division. It focused on racing engines and one car in particular: the 3.0 CSL.

With 270kW from a 3.3-litre straight-six -- and weighing a mere 1.1 tonnes -- it won everything European touring car racing had to offer. 

A few years later, BMW wanted a car to compete in a Formula 1 undercard race and made a mid-engined supercar called the M1. To meet the rules, it had to build at least 400 road-legal versions. As well as a stunning shape, the M1 was the fastest German sportscar of the time. Just 456 were made, so it's very collectable now. 

That car gave the division its name and within a few years it was turning out the M3 and M5 performance variants that cemented BMW's reputation as a driver's badge. When it applied M-ness last year to the 1 Series two-door, it wanted to reserve “M1” for the 1970s original -- or its heirs -- so it broke with convention and called it the M Coupe. 

Which suggests that behind the scenes BMW may be working on a new M1 supercar. In a way, that's exactly what it needs because the blue, violet and red tricolour is being applied increasingly liberally across almost everything BMW makes. 

That M Coupe saw the division embrace turbocharging for the first time, but any inhibitions about how far M could legitimately go had already been dismantled a couple of years earlier when it allowed offroaders, inherently non-racy vehicles, to qualify for performance tuning.

The X5 M and X6 M were the result; amazingly capable SUVs but a long way from where it all started. There's more. To maximise the potential of the badge, there's now a sub-brand called M Performance. This is sort of M-lite, with a performance wand waved over the chassis but assembly on the standard line rather than specialist construction.

VALUE

The prices start from $68,400 BMW M135I, $292,500 BMW M6 (coupe) and $308,500 (convertible). Its debut vehicles are powered by M's first diesel, a triple-turbocharged six-cylinder in the M550d versions of the X5 and X6. BMW admits this diversification was inspired by the success of its M Sports packages, which apply racy cosmetics such as sports seats and aero kits to standard cars.

M Sport versions have just become available for the 3 Series launched early this year and BMW expects 40-50 per cent of buyers to opt for it -- on a car already available with a so-called Sportline trim. Depending on which model you start with, this can add $8900 to the price.

M Performance parts are the latest twist. They leverage the M Performance sub-brand to offer buyers a selection of aftermarket add-ons. In effect, the M badge has been parlayed into a huge Sports-R-Us superstore. If it used to stand for Motorsport, perhaps it now stands for Marketing.

In fact it's difficult to say what it stands for, so diverse are the offerings. The two latest are effectively bookends for the non-cosmetic side of operations. At one extreme is the M135i, an M Performance model that spices up the mainstream hatchback launched last year.

For the price the M135i’s performance is sensational: 4.9 seconds to 100km/h (slightly slower with the manual). That's identical to the M Coupe, which was $30,000 more. At the other is the M6 Coupe or Convertible, which is the most expensive M you can buy and, aside from the V12-powered long-wheelbase 7 Series limousine, the most expensive BMW.

TECHNOLOGY

Only a year after it debuted in an M car, they both use turbocharging. Thanks to emission regulations, turbocharging is needed to meet the challenge of getting performance and economy from smaller capacity engines. In M cars, it changes the character of their power delivery. Previously, you had to rev the daylights out of them before you could tap into their potential. With turbos delivering huge torque virtually from idle, that's no longer the case.

It has made the M6, which is a mechanical twin to the M5 launched earlier this year, much more like its AMG rivals from Mercedes. The engine, downsized from the previous 5.0-litre V10 to a 4.4-litre V8, uses turbos to get 39kW more power and a whopping 160Nm more torque. The redline arrives 1000rpm lower, at 7200rpm, but peak torque is accessible across virtually the entire rev band, from 1500-5750rpm.

It's some compensation for turbocharging's downside: lag between throttle and response. But what it means in practice is wheelspin on demand and power oversteer if you turn all the settings to max and take it to a track, as BMW did for the launch.

The M6 Coupe can hit 100km/h in 4.2 seconds and twice that in just 12.6, making it BMW's fastest car. The Convertible, being heavier, is a fraction slower but still quicker than its rivals from Jaguar or Maserati. Of course, there's an option called the M Driver's Package, which lifts maximum speed from an artificially limited 250km/h to 305km/h. I've little doubt it could get there.

DESIGN

The Convertible is heavier and less rigid than the carbon-fibre-roofed Coupe, but they are both the wrong side of 1.9 tonnes. The M6 has piled on 200kg since the 2006 original. It's a splendid luxury express with one of the best cabins I've seen in a BMW. However, it's a long way from where M started and although everything works -- the brakes held up well, for example -- I wanted to be less remote from the car.

That's something you get more of in the M135i. Even though this is not a full-dose M car but an M Performance model, it's closer to the first M3 than anything bar the M Coupe mentioned above -- which is now, sadly, unavailable. The M135i looks like a frumpy little hatchback rather than a performance car and, initially, seems too softly sprung for a performance variant.

DRIVING

The Lakeside circuit in Queensland is much tighter and twistier than Phillip Island, where it took the M5. Any overzealous throttle use brought the tail out and the traction control light was almost permanently on. Disappointingly, there was less subtlety and feel to the steering, throttle and brakes than I'd like and where the M5 was a hoot at Phillip Island, the M6 felt large and weighty at Lakeside. 

I was acutely aware my daring depended on fat rubber and it seemed like hard work from behind the wheel. No wonder, given the speeds achievable. However, brilliant front-end grip means you can point it around corners with confidence. The rear can stutter a little, but it tracks through bends with superb composure. It's also relatively light, at 1.5 tonnes.

The M135i’s engine -- a familiar 3.0-litre turbo six -- sounds great when pressed and comes with an unsampled six-speed manual or excellent eight-speed automatic. There are issues, such as tyre noise and wide A-pillars, but against rivals such as the Audi S3 it looks an absolute bargain.

VERDICT

With more M cars on the way, including an M3 Coupe and Convertible rebadged as the M4, it's a vital reminder of where the whole M thing started.

BMW M135I

Price: from $68,400 
Engine: 3.0-litre turbocharged 6-cylinder petrol, 235kW/450Nm
Transmission: 6-speed manual or 8-speed automatic, RWD
Thirst: 8.0L/100km

BMW M6

Price: from $292,500 (Coupe) to $308,500 (Convertible) 
Engine: 4.4-litre turbocharged V8 petrol, 412kW/680Nm
Transmission: 7-speed automatic, RWD
Thirst: 9.9L/100Km (10.3L/100Km)