YAHOO AUTOS
How does it work?
More than any other new vehicle, the BMW i8 requires this explanation up front — not just for the dull process of turning energy to motion, but for the whole enterprise of a $135,700 supercar designed for maximum eco appeal with styling from the 23rd century.
And last week, I was among the first to find out.
In BMW engineer speak, the 2015 i8 is properly called a “plug-in electric hybrid sports car” — one with a 129-hp electric motor driving the front wheels and a turbocharged,1.5-liter three-cylinder engine with 228 hp driving the rear axle.
Since I last drove a prototype of the i8 in August, some fine-tuning of the all-important software and electrical power unit has been done by the Munich madhatters, but the i8 remains the giddy thrill and conversation piece it was then.
I can already sense the comments that 357 hp and 420 lb-ft of torque for a $137,000 car is, like, a complete rip-off, man. That someone can buy two Ford Mustang Shelby GT500s for the price, blow an i8 away when the light turns green, and put the rest in a bank account.
I wish them peace and happiness with this, but pure speed isn’t the point of the i8, although it can hustle to 60 mph in 4.2 seconds or less when set up in Sport mode.
The i8 looks like no other car, and its complex drivetrain (with two transmissions, a lithium-ion battery pack and more software than the starship Enterprise) leaves us grasping for comparisons. Up in the hills and pushing it hard, the i8 did pretty damned well in upholding BMW’s ancient mantra of “ultimate driving machine.”
As I rolled along around the wealthier provinces of Southern California, I eventually came to one that made some sense. In overall performance and feel, I kept coming up with the smaller and lighter 321-hp Porsche Cayman S — though the Cayman S is dynamically the superior car and rather dramatically less fuel efficient depending on how I drive it.
While the front e-motor gets a two-speed transmission – first gear good up to 75 miles per hour, second on up to the 155-mph maximum – the rear gas engine gets a six-speed automatic you can leave to shift by itself or which you can shift manually via the console lever (only in Sport) or by using the steering wheel paddles.
Once I got all the various new drive rhythms of the i8 imbedded in my subconscious and inner ear, the play time up and down the gears was entertaining. Both the electro-mechanical steering and adaptive dampers of the suspension are outstanding.
But there were a couple of refinement issues for me (and for other testers) on these launch cars that caused healthy conversation. The first one was the less than seamless transitions when going from the 129-hp front-wheel-drive eDrive to the all-wheel-drive 357-hp parallel hybrid mode in either Comfort or Sport.
There is a slight feel of driveline shunt every so often, and I mean slight, but enough of it to make me wrinkle my nose whenever it happens. Between the software, the central electric brain, and a secondary 15-hp e-motor attached to the rear engine to in part help with these transitions, every so often an order or two gets missed.
Then, when a wheel happens to leave the pavement over a bump while in motion in the all-wheel-drive parallel hybrid state, the brakes blip on the axle with the momentarily lifted wheel. The subsequent resumption of normal all-wheel motion after all rubber re-meets the road can be less than smooth.
The BMW engineer in charge tells me that the near full arrest of rotation on the one axle is done as a safety measure, in order to protect the drivetrain against the possibility of the lifted wheel or wheels spinning freely and risking damage to the system, since there’s no mechanical link between front and rear.
Again, this needs a little tweaking, and I was assured that the software changes will carry on once i8 deliveries begin.
In straightforward momentum and handling, the i8 takes your sports car thrills to a different level. One of the more serious bits to decide was what tires to use, since the i8 needs to be a thrilling driving machine and not an extremely suped-up Honda Insight.
BMW i has elected to give journalists the wider and less tall optional set of 20-inch tires to test – 215/45 front and 235/40 rear. These Bridgestone Potenzas do a good job overall, even while promising less rolling resistance and, in theory, less lateral grip.
The logic in these skinny 20s is: what one loses in width of footprint, one gains in footprint length.
Added assistance comes in no small part from a micro-managing stability control that is smooth in these conditions over good pavement. Any lateral slip movement is relatively neutral and what little controlled tail wag happens gets wrangled well without killing the fun. Weight distribution is 47 percent front and 53 percent rear, which also helps in keeping things handled even if grip limits are exceeded.
Another big helper dynamically is the low stance of the i8. The central rotational point of the is just 17.8 inches from the ground, the lowest of any BMW by a good bit. This and the natural ultra-stiffness of the underlying aluminum and carbon-composite body and chassis make for an extremely satisfying sports car in any pilot’s hands.
I do enjoy the i8 design inside and out; the only exterior bit that might wear on the eyes after a while of looking at it being the very busy rear end fascia.
It didn’t take long for it to seem like a scowling Transformer-bot staring at me. But go for the pricy Pure Impulse trim – sorry, world – and the darker exterior detailing takes some of the scowl away from the contrasting color scheme everyone was testing this day.
The slick front seats look the part, but could offer just a little bit more lower back support and side support during the most assertive driving moments.
Sadly, the rear seats of this 2+2 sport coupe are utterly useless for anyone over horse-jockey tall – even more so than in a Porsche 911. Leg room is actually acceptable back there, but, if you want rear seating for average humans with heads, wait for the spider version of the i8 that’ll have those rear passengers singing the praises while catching flies in their teeth.
The roughly 6 cubic feet of luggage space in the rear is also tight, though two gym-style weekend bags could be wiggled in to fit. BMW i and Louis Vuitton have designed an optional carbon fiber themed custom set of luggage to look good and to fit into every nook and cranny perfectly.
It was ultra sunny by the ocean and the large rear thermal glass could have been doing a better job; the hard plastic bits in back became scorching hot to the touch.
How green is it? It’s always tough to say, and EPA figures were yet to come at the time of this test, but the European numbers should theoretically translate into a hybrid-mode Eco Pro figure of around 35 miles per U.S. gallon.
The lithium-ion battery pack that sits the length of the central tunnel through the passenger cabin has a 5.2 kWh useable capacity and can get a full recharge from the extra-cost wall box in as little as 1.5 hours, or up to 2.5 hours from a household outlet.
Driven shrewdly under appropriate road conditions, the battery energy can be replenished while in motion in as little as ten minutes via the rear three-cylinder engine and/or while under lightest throttle in the flatlands. Full electric driving can power 22 miles when not exceeding 75 mph.
So, your mpg figure will vary widely depending on how you drive and the topography in your area. Clever hyper-milers could easily reach 60 mpg or more — just don’t drive behind these folks if you are susceptible to road rage.
If it’s any indicator, my i8 managed to not only dramatically upstage a Bugatti Veyron parked along legendary Highway 1 in downtown Malibu, but did the same alongside a newly delivered Tornado Orange McLaren 650S spider.
Who knows how many more heads will turn once the optional carbon composite wheelset, and laser headlights come online by the end of 2014?
Not to mention the i8 spider — which should arrive just as the valets of high-end hotels tire of parking the i8 coupe out front. The new age of BMW supercars has arrived, and it works quite well.
Full disclosure: The manufacturer provided meals, air transportation and lodging in California for this review
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