Quick Summary:

The 2014 BMW i8 is one of those rare machines that's even more stunning and desirable in production guise than it was as a concept car. It's also jaw-droppingly quick and profoundly stable on the tightest and most challenging canyon roads. We want to get down on one knee and ask it to spend the rest of its life in our garage.

What's more, this supermodel of a supercar is also a plug-in hybrid. With a fully charged battery it supports a mild-mannered electric vehicle mode that lasts for some 20 miles. The BMW i8 represents simultaneous cake ownership and consumption to those who can afford its estimated base price of $136,650.

What Is It?

The 2014 BMW i8 is a plug-in hybrid two-door sports car with supercar proportions. The lithe bodywork that has us so entranced is, in fact, a collection of lightweight and dent-resistant plastic panels that have been carefully sculpted with numerous functional aerodynamic details.

That plastic skin conceals a lightweight carbon-fiber chassis that comprises the entire passenger cell in much the same way as the 2014 BMW i3 all-electric vehicle we drove recently. As we saw in that car, aluminum subframes sprout from either end to support the suspension and powertrain.

Make that powertrains, because the i8 has two of them. An electric motor resides up front and powers the front wheels to the tune of 129 horsepower. There's also a 1.5-liter turbocharged three-cylinder gasoline engine, but it sits crossways in back and sends its 228 hp to the rear tires through a six-speed automatic transmission. The two ends can deliver a combined output of 357 hp and 420 pound-feet of torque to the pavement when the need arises.

The i8's passenger compartment is split down the middle by what would be called a transmission and driveshaft tunnel in any normal car. But here in the i8 that space is instead filled by a lithium-ion battery pack with 5.1 kilowatt-hours of usable capacity. The rated capacity, the figure you'll need to calculate your federal tax credit, is 7.1 kWh.

How Does It Work?

That central battery pack can be fully recharged at home through a standard 120-volt garage outlet in about 3.5 hours. Upgrade to 240-volt SAE-compliant charge equipment (or visit a public station) and you can trim that down to about 1.5 hours.

From there, select EV mode and the i8 moves out as a silent-running front-drive electric vehicle. The front-mounted electric motor becomes a generator when the brakes are applied, which recovers a portion of that energy and plows it back into the battery. According to BMW the i8 can stay in EV mode for up to 22 miles, but the official EPA range figure has not yet been released.

Because it's a plug-in hybrid, the i8 doesn't coast to a halt when the battery runs down. Instead, the three-cylinder gas engine springs to life and starts pushing from behind through the six-speed gearbox. This change-over heralds a switch to the default Comfort mode.

In this mode a small fraction of the engine's power is siphoned off by a small belt-driven generator (which also functions as the starter motor) in order to maintain the battery at a level of three miles' worth of juice. This minimal level of battery power allows the engine to go dormant at stoplights and let the front-mounted electric motor get the car going again when the light goes green. It also enables the i8 to creep about electrically in parking lots. There's even enough for the electric motor to pitch in and bolster the engine's output for short bursts of acceleration.

But you'll need to switch into Sport mode if you're planning to do much of that, if you want the full power of both powertrains for extended periods. Among other things, Sport mode uses the belt-driven generator to greater effect to elevate that battery to about 12 miles of juice.

It may not sound like much, but the difference is massive. Our local canyon roads have places where all 357 hp can be unleashed for a time, but then a corner looms and it's time to roll off, balance the car on the brakes and turn in. Other times the gradient shifts downhill and we must nuance the throttle or back out entirely. During these periods (and there are more than you'd think) the engine's little belt-driven generator goes about its business while the front-mounted electric motor-generator gobbles up braking and coasting energy.

No matter what the terrain or the pace, every time we glanced down at the range meter in Sport mode it read the same: 12 miles.

How Does It Drive?

In EV mode the i8 is relaxed and serene and gives off no hint of its potential. The throttle is buttery-smooth and the brake pedal feels natural and progressive. But there's very little propulsive noise except for the faint keening of the electric motor and the regenerative braking, sounds that any Prius owner would recognize instantly.

The picture changes slightly in Comfort mode when the engine comes to life. The growl of the three-cylinder motor isn't objectionable or overly loud, but we're so used to the cadence of four or six cylinders that three draws a little attention to itself. It makes plenty of power, though, and the six-speed transmission shifts smartly yet smoothly.

Sport mode brings with it a rush of acceleration when we rev the engine up toward its 6,500-rpm redline in Manual mode and flick up and down through the gears with the steering-mounted shift paddles. At our test track, the i8 sprinted from zero to 60 mph in 4.5 seconds (4.2 with 1 foot of rollout as on a drag strip) and completed the quarter-mile in 12.6 seconds at 111.8 mph. These numbers represent a near dead heat with our departed 2013 Tesla Model S long-term test vehicle, which streaked to 60 mph in 4.4 seconds (4.1 with rollout) and arrived at the end of the quarter-mile in 12.6 seconds at 108.4 mph.

At speed, the boosted three-banger begins to sound like a finely tuned machine, as if it suddenly grew three more cylinders and became a howling V6. Some of this is electronic trickery. There's an electronic noise actuator under the rear deck lid, and specially designed sounds are emitted from the stereo's rear speakers (whether it's switched on or not). Think of it as the opposite of Active Noise Cancellation. Frankly, we don't care if the exhaust note is essentially being auto-tuned, because the result is fantastic.

And then there's the handling, which is exceedingly brilliant. The balance is impeccable, with just a slight whiff of understeer at the limit, and its steering is both accurate and direct. It's an electric-assist system, which filters out the raw coarseness of the asphalt texture that some might mistake for road feel, but the build-up of effort is so well matched to the cornering forces that the driver knows exactly what is going on.

Part of the i8's cornering prowess comes from its very light weight, which registered 3,382 pounds on our scales, and near-perfect weight distribution of 49 percent front, 51 percent rear. BMW would add that the i8 also has the lowest center of mass of any car it has ever produced. And then there's the matter of the dual powertrains, which makes the i8 an all-wheel-drive machine with a sophisticated control system that can continuously vary the output at either end to balance the car. That's a big part of the magic right there.

The i8's balanced and engaging feel on real roads doesn't translate to total domination at the track, where the limits of the skinny 215/45R20 front and 245/40R20 rear tires come into play. The poise is still there, and there's nothing wrong with 0.93 g of lateral grip, a 67.0-mph slalom speed and a 108-foot panic stop from 60 mph. But there's no denying that these numbers lag behind those of track-ready supercars.

But that's not quite the point. The BMW i8 is, after all, a plug-in hybrid. It has a slightly different mission.

How Does It Rate in Terms of Comfort?

You climb inside after first lifting the i8's finely counterbalanced scissor doors. It's a 2+2 that technically seats four, but your rear passengers are most likely to be suitcases because the rear "seats" are uncomfortably tiny and because trunk space is a paltry 4.7 cubic feet.

Out of necessity, the carbon-fiber chassis produces a high sill that isn't friendly to short skirts. The best way to get in is to sit on the sill, swing a leg over, allow your backside to slip into the seat, then follow with the other leg. It's not hard once you master the move, as long as you also remember to duck under the bottom edge of the door at the same time.

Once inside, the cockpit is at the same time inviting and driver-oriented. The multi-adjustable power seats offer good support and long-distance comfort, and our 6-foot-2-inch tester fit with headroom to spare. The center stack sits at an angle of 12 degrees, which puts everything close at hand. The shifter and all-important mode switches are close by, too, and each selection changes the background color and meter design of the main instrument pod.

The dials turn blue in EV mode; Sport is red and Comfort is gray. None of them is particularly attractive or easy to read, though, because the numbers are small, the moving needles are skinny and they don't contrast strongly enough with the background. We found ourselves relying on the head-up display instead.

The suspension rides on two-mode dampers that use a standard setting in EV and Comfort modes and a firmer setting in Sport mode. The base setting is only slightly firm in town, but Sport crosses the line at city speeds. Push the car hard in the sort of driving Sport was intended for, however, and this firmer setting comes into its own, absorbing large bumps and small ripples with apparent ease.

What Body Styles and Trim Levels Does It Come In?

U.S. buyers of the 2014 BMW i8 have it easy. There's only one i8 and everything is standard, including the wider 215/45R20 front and 245/40R20 rear tires that are an optional upgrade in Europe.

The 2014 i8's announced base price is $136,650. The only variations have to do with the interior, which is offered in four "worlds": Mega, Giga, Tera and Pure Impulse. Mega is the standard offering, and it puts a focus on sustainable materials. Our test car was equipped with the $2,000 Giga package, which adds perforated leather seats and LED headlights. Next up is Tera, which sells for $3,000 and includes unique leather materials tanned with plant extracts. From there it's a big jump to the $10,800 Pure Impulse package, which brings with it an array of exclusive interior material upgrades on every surface.

Laserlight high-beam headlights will eventually be offered as an option once they get approved by federal regulators, but the availability date (and price) is as yet unknown. BMW says they illuminate the road ahead for 2,000 feet instead of the still-impressive 1,000 feet covered by the standard LED setup.

How Safe Is It?

The 2014 BMW i8 is an all-new model that has not been crash tested by NHTSA or the IIHS. And it's not likely to undergo such tests in the future, either, because of its high price and exclusivity.

But carbon fiber has proven to be a very strong structural material in the high-risk world of auto racing, and the front and rear suspension subframes are made to absorb crash energy. There's no reason to expect any vulnerabilities.

What Kind of Mileage Does It Deliver?

Official EPA mileage and electric range ratings have not been released, and BMW engineers are not prepared to issue any estimates just yet. They have said the electric range could be 22 miles, but this number wasn't derived from U.S. test methods. We figure the final U.S. figure might range between 18 and 20 miles.

As for gasoline, the fuel tank holds 11 gallons, and the estimated range is 320 miles. EPA combined gasoline fuel economy may well settle somewhere between 26 and 28 mpg. Of course, plug-in hybrids only use fuel after the battery has run down, which means the amount of fuel ultimately used will vary widely on a case-by-case basis. It could be zero with a short enough commute and frequent enough recharging.

What Are Its Closest Competitors?

The BMW i8 is an unusual car with few, if any, direct peers. But there are some competitors, though the specs don't match up the same.

The Tesla Model S is the car that naturally comes to mind because it shares the exclusivity, brand image and green tech aspects. But the Tesla is a pure electric vehicle, not a plug-in-hybrid. Its cross-country potential is tied to the placement of Tesla Superchargers. It's also a very spacious and comfortable car that seats five full-size adults and their luggage.

The Porsche 918 Spyder is a similar sort of plug-in hybrid, but its gasoline engine is far more powerful and it's a true monster on the racetrack. It also costs $850,000. Nope.

Why Should You Consider This Car?

The 2014 BMW i8 is a driver's car that puts a premium on handling. It's a technically interesting machine that just happens to deliver supercar looks for less than supercar money. It's more exotic than the Tesla Model S, and it carries the BMW nameplate and all of the heritage, quality and dealer network that goes with it.

And as a plug-in hybrid with a modest battery, it's also a good choice for those buyers who can't provide 240-volt charging at home or would simply rather not deal with the limitations (real or imagined) of a fully electric vehicle like the Tesla Model S.

Why Should You Think Twice About This Car?

Those high carbon-fiber sills may present entry and exit problems for folks who aren't as flexible as they once were. Take a test-sit if you have doubts.

Drivers who hope to carry more than a single passenger should look elsewhere because this backseat won't hold adults. And the pitiful trunk is tinier than a Miata's; that unused backseat may be the only place to stash luggage. Even BMW recognizes this. It offers custom-fit luggage that straps to the backseat, but it's from Louis Vuitton and costs a small fortune.

Of course, anyone who wants no part of gasoline and would rather have a high-status all-electric car should know that the Tesla Model S is still their only choice unless they want to downsize to the 2014 BMW i3.

Edmunds attended a manufacturer-sponsored event, to which selected members of the press were invited, to facilitate this report.