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BMW's plug-in i8 blends sporty with efficiency, if you treat it right

BMW went back to the drawing board to come up with the i8, a car with three motors, four seats, all-wheel-drive, and a swooping exterior that's straight out of the future. Our first impressions on the road.

Tim Stevens Former editor at large for CNET Cars
Tim Stevens got his start writing professionally while still in school in the mid '90s, and since then has covered topics ranging from business process management to video game development to automotive technology.
Tim Stevens
6 min read

While other manufacturers are messing about, slowly tuning and tweaking plug-in hybrid systems and waiting to see which way the market shifts, BMW has been toiling away to do something more radical, launching an entire new brand focused on alternative means of propulsion. Its first release from the "i" brand, the i3, is a little EV city car that impressed us when we got a chance to test it out last year. For its next trick, the company created something completely different. It's a bit more traditional in some ways, far more radical in others.

The 2015 BMW i8 looks like an automotive artifact from the future (pictures)

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It's the i8, a plug-in hybrid designed from the ground up to be just that: a plug-in hybrid. It offers two motors, the more traditional being a 1.5-liter, three-cylinder, turbocharged, gas-powered lump that pushes 228 horsepower and 236 pound-feet of torque through the rear wheels. (It's a variation of the motor in the Mini Cooper.) In the front is the so-called eDrive motor, a tweaked version of that found in the i3, here producing 129 horsepower and 184 pound-feet of torque. This time it's also running through a two-speed transmission, while there's a six-speed auto box at the rear. (The i3 needed only a single gear.)

BMW i8
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But wait, there's more. To make up for the turbo lag caused by the oversized impeller mounted on the 1.5-liter, a similarly up-rated starter has been installed that not only provides for battery charging and start/stop functionality, but can act as "eBoost" to fill the torque gap when accelerating quickly. This provides another 11 horsepower and 37 pound-feet of torque.

All-told, between the two main motors, the car offers 357 horsepower and 420 pound-feet of torque, but not all the time. Fully-charged (which takes just 90 minutes on a Level 2 charger, or 3.5 hours in a standard 110 outlet), you can cover up to 22 miles at a top speed of 75 in eDrive mode, using just the electric motor. Comfort mode is the default setting, which uses both motors as needed, while a sport mode is there too, which always has the rear motor running and ready.

When it isn't needed for power, the 1.5-liter engine acts as a generator, maintaining the 7.1 kilowatt-hour battery pack that runs along the spine of the car. Batteries sit where a driveshaft would normally be in an all-wheel-drive car, but here you get all the benefits of power on all four corners without a transfer case sitting in the middle, causing friction losses. At least, that's the theory, but sadly our testing was limited to dry asphalt in perfect weather. Hopefully we'll be able to try out the AWD in conditions with less grip in the future.

BMW i8
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So how does it drive? To answer that you first must get into the thing, which requires a bit of technique. Not unlike slotting into an '80s supercar your best avenue of approach is to fall backwards into the seat and then pivot your legs in over the wide, high door sill. From here, it's a bit of a reach to pull the scissor doors down, but they close cleanly and with a satisfying thud.

Front seats are comfortable and have basic power adjustment, but they lack the sort of infinite customization found on BMW's more traditional sedans and coupes, not even offering adjustable lumbar support. (Rear seats, meanwhile, are perfectly suitable for small children and circus performers.) The cabin is somewhat simple looking, rather more familiar than the relatively exotic accommodations afforded by the i3, but clean and mostly well put together. Materials feel very good, and controls fall easily to hand. However, we can't help but be disappointed by the lack of storage in here. There are no door pockets (for obvious reasons) nor even a glovebox. All you get are a pair of small, shallow compartments in the center console suitable for a wallet, a phone, and little else. (There's also a small trunk in the back that'll manage an overnight bag. Maybe two.)

BMW i8
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A standard shifter sits between the seats for toggling gears, rather than the dashboard twist mechanism found on the i3, and there are also paddles mounted to the wheel for when you want to try and boss the transmission around. The wheel itself is comfortably fat and leather-wrapped, sitting before an LCD display cluster that offers plenty of info. It also changes from blue to orange when you toggle Sport mode. Sporty.

We started in eDrive mode, however, and the experience there is quite good. There's plenty of power for zipping into openings in city traffic if you like, and even a short highway jaunt wouldn't be out of the question. Shift into Comfort, or put your foot all the way to the floor, and the gasoline engine lends a hand. This isn't all too dissimilar to the Chevy Volt, but where the Volt makes an awful, groaning sort of sound when the motor spins up, the i8's engine actually sounds good.

Mind you, there's some digital trickery going on here, a microphone in the engine compartment serving to pipe engine sounds in through the car's stereo system. This sort of shenanigans is a bit unfortunate, and unfortunately cannot be disabled, but to reluctantly give credit where credit is due, it works. In Sport mode, give the car some throttle and you'll be greeted with a surprisingly throaty growl that you wouldn't think could come out of such a pint-sized lump. It passes the "windows down in the tunnel and gas it" test with ease.

BMW i8
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As does the acceleration. In Sport mode the car is plenty peppy, not offering anywhere the poke of BMW's higher-powered sports sedans, but giving a nice blend of EV-style throttle response and gasoline-powered speed. If only the transmission would keep up. In our brief drive, even in "manual" mode, the car up-shifted when it wanted and refused to downshift even with the digital tachometer showed plenty of room to do so. It's not a car to be hurried in this fashion.

In the twisties, the i8 does an admirable job of hiding its 3,285 pounds, but is ultimately let down by relatively skinny 215/45 R20 tires up front. (245 section-width at the back.) The car dives into corners readily, but it isn't long before the Bridgestone Potenzas are squealing uncomfortably and the front is washing away. It's a gradual, progressive sort of thing, an almost reassuring signal that you've found the limit, but we can't help wonder how much better this car would be with tires that prioritized grip over rolling resistance and fuel economy.

2015 BMW i8 looks like a future classic (pictures)

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Speaking of fuel economy, the i8 is rated at a remarkable 94 miles-per-gallon in Europe. The EPA hasn't weighed in just yet, but don't expect to get anywhere near that if you drive aggressively. In a day of admittedly hard driving, we averaged just 22.6 mpg, a figure that would likely be easily achievable even in something like an M3, never mind any of BMW's diesel offerings.

Again, that was driven hard, and we'll withhold judgement on this thing's claims to being an economical sports car until we get to live with one for a few days and give it the proper review treatment, but that figure is admittedly a bit disappointing, even for hard driving. The price, too, is something of a bitter pill: $135,700 to start, though unlike a traditional BMW there won't be many options to drive the price up from here. It's a very well-equipped car.

BMW i8
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And a great looking one, too. From a distance the silhouette is almost traditional, but look closer and the details are striking. Most dramatic is what BMW calls a "stream flow wing" at the rear, with channels cut into the fenders and swooping under the rear glass. BMW tuned every surface of the thing to an extreme degree, offering just a .26 coefficient of drag, the slipperiest BMW ever. That's the same as a Toyota Prius, for the record, and very close to that of a Tesla Model S.

But is the exotic look and drivetrain enough to justify the exotic price? We look forward to reporting back after we've had enough seat time for a proper review.