Sunday, September 29, 2013

New BMW I* rating



Just a handful of hard laps on the flowing road course at the Miramas circuit in the south of France in a BMW i8 is enough to tell you what an incredibly unique sportscar this. Unique, not because it’s an advanced hybrid or because it’s made from carbon fibre, but simply because of the way it drives – it feels superglued to the road like no other sportscar I have driven. And it’s all down to weight distribution. Forget the 50:50 balance, which is a given in any BMW – what gives the i8 its inimitable dynamics is that the weight is all concentrated within the wheelbase and skewed right down the floor of the carbon-fibre body shell.



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Like with most hybrids (and especially EVs), the biggest enemy is weight, thanks to the hefty battery pack and electric motor. To offset the weight of the hybrid powertrain, BMW has used a lightweight carbon structure for the body and aluminium for the sub-frames, resulting in a kerb weight that, according to BMW, is less than 1,490kg. By supercar standards the i8 is still no featherweight, but it’s the way BMW has juggled the weight – using ultra-lightweight bits in the top of the car whilst keeping the heavy bits low down – that has given this sports coupé its incredibly low centre of gravity.
The 94kg battery pack, for example, sits inches off the floor in a protective housing and is carefully placed to get the best front-rear balance. The compact 228bhp, 1.5-litre, three-cylinder petrol engine in the BMW i18 sits just ahead of the rear wheels, whilst the 96kw (129bhp) electric motor sits just behind the front axle, again for the best weight distribution. BMW has saved the carbon-fibre bits for areas like the roof and body panels to avoid raising the centre of gravity.
The i8 from BMW looks like a sportscar for the future. The stretched kidney grille makes sure that you don’t mistake this low-slung coupé for anything other than a BMW, but it’s at the rear where things get interesting, with the sharply cut haunches and flying buttresses creating a layered effect. Also very sci-fi are the butterfly doors that swing open to reveal the cabin. The familiar iDrive controller and gear selector are present and the interiors look futuristic. The i8 is the first production car to use high-tech Gorilla Glass – the kind that’s used on cell phones – on the rear screen for sound insulation. This thin piece of glass (to save weight) is scratch resistant and incredibly tough.
Starting the stunning-looking BMW i8 is a bit of an anticlimax, because it doesn’t fire up like a conventional sportscar. Press the Start button and there’s no whirring starter motor, but instead a soft chime to tell you that you’re ready to go.
BMW’s familiar driving modes are carried over, and the default setting is Comfort – the middle of three hybrid settings. With the battery sufficiently topped up, you can pull away under electric power alone, the compact motor driving the front wheels. Press the throttle a touch more and the petrol engine behind you immediately kicks in and the result is a combined 357bhp driving all four wheels.
The way the three-cylinder engine revs is pretty smooth but not entirely seamless. There are some noticeable jerks when drive to the rear wheels is engaged, but BMW’s engineers say they will certainly iron those out before launch. 
In Sport mode, the 1.5 motor doesn’t disengage, and what you get is max performance along with sharper steering and throttle response. Acceleration is fantastic and you can easily believe the 0-100kph claim of 4.5 seconds. But it’s the utterly seamless way the i8 rockets forward that is quite fascinating. There is no lag at all, and with the electric motor delivering max torque instantly, you can feel a strong and linear tug. The accompanying sound, unfortunately, isn’t too exciting and, whilst the thrummy three-cylinder engine has been made to sound sporty, there’s a fair bit of whine from the electric motor. 
The BMW i8’s handling is what simply blows you away. With a low polar moment of inertia (thanks to all the weight being concentrated in the middle of the car) it feels incredibly agile and changes direction faster than a confused mamba. The electro-mechanical steering is remarkably direct and the overall balance is completely neutral. Upping the pace and pushing hard into corners, the i8 felt like it was on rails and, near the limit, there’s just a hint of understeer. The fact that there’s hardly any body roll through corners has allowed BMW to get away with using skinny 215/45 tyres in front, because the i8’s flat poise ensures a wide contact patch. The i8 rides on extremely lightweight 20-inch aluminium wheels that have been designed for aerodynamic efficiency.  
BMW is on to something big with the i8. It’s intriguing and completely unconventional, which is a huge part of its appeal. And let’s not forget the i8’s green credentials, for which BMW has invested in cutting-edge tech. The proof of the pudding will be the 40kpl figure the i8 is expected to give in the European driving cycle. 
However, genuine enthusiasts will be blown away by the way it handles, which makes it utterly addictive to drive. At its heart, the i8 is a BMW, but this one could make even Sunita Narain smile when it comes to India in mid-2014.    
Mithlesh Chaubey
PGDM-I

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