Continue reading A Semi-Authorized Guide to BMW Innovation…
The Turbocharged Four-Cylinder Makes Its Triumphant Return
It’s been almost 40 years since BMW released the 2002 Turbo, and until now, turbocharged four-cylinders from BMW have been nonexistent on U.S. shores – save the lone 1983 F1 race in Long Beach. That’s set to change later this year when BMW brings its all-new turbo’d 2.0-liter to the States as its entry-level engine.
Despite the misleading name of TwinPower, this new four-pot is only packing one turbocharger (a twin scroll unit) and fitted with direct injection, double VANOS variable camshaft technology and VALVETRONIC variable valve control. The result is 245 horsepower (up 15 hp from the current 3.0-liter inline-six) and 258 pound-feet of torque (up from 200 lb-ft), available at an oh-so-low 1,250 rpm.
Combined with a choice of either a six-speed manual or the eight speed automatic pulled from the 5 series GT, a dual mass flywheel, electric water pump, a 14 mm offset crank, start-stop tech and an LDS coating that reduces weight and improves cooling, overall efficiency is up and fuel consumption and emissions are down. Fitted to the new X1 xDrive28i, the math adds up to 7.9 liters of fuel per 100 km, or just under 30 mpg on the U.S. cycle.
When is this new four-pot coming our way? BMW is set to announce the first U.S. vehicles to get the new turbocharged 2.0-liter at this month’s New York Auto Show, but the smart money is on the 3 Series and X3, along with the entry-level 128i.
A Modular World and a New Six-Cylinder Diesel
The cheesetastic video above is a good illustration of what BMW has planned for its new modular engine family, and die-hard Bimmerphiles should be happy to see that the inline-six isn’t going away anytime soon.
Instead, BMW is developing a range of three-, four- and six-cylinder gasoline and diesel powerplants all created using the exact same architecture. The result is lower cost and increased efficiency, with each gasoline-powered cylinder putting out between 40 and 67 hp, along with 44 to 73 lb-ft of torque. The new diesel mills will output between 26 to 53 hp and 55 to 73 lb-ft, with the aluminum crank case, accessory components, oil pan and intake tract all shared by both the diesel and gasoline engines – a total of around 60% of parts. This standardization of engine components is sure to help BMW’s bottom line, but the new rear-mounted chain drive is sure to give amateur wrenchers a headache.
On the plus side, BMW’s new 3.0-liter turbodiesel has the potential to continue our love affair with BMW’s oil-burning six-pot, with an output of 258 hp and a silky wave of boosted torque – 413 lb-ft of the stuff – available from 1,500 rpm onward.
The Next 1 Series and a Glass-Roofed Sixer
When we were shuttled into BMW’s R&D center, they taped up our cameraphones and confiscated our DSLRs, but that didn’t stop us from catching a glimpse of the refreshed 1 Series and an oddly camouflaged 6er.
The 6 Series prototype we spied from high atop the central building looked exactly like the drop-top we’ve already sampled and the coupe that’s debuting at the Shanghai Motor Show. However, BMW appears to be working on a glass-roofed version to slot in between the two. We’re not sure if it’s packing the same kind of “Magic Sky” technology as the recently introduced Mercedes-Benz SLK, but judging by the tint, we wouldn’t be surprised if BMW had something similar up its sleeves.
More importantly, several refreshed 1 Series prototypes were out and about, and it looks like the mid-cycle update will primarily be comprised of a new rear bumper and taillamp design, coupled with a more upright front fascia and grille that apes the reworked 5 and 7 Series. BMW officials wouldn’t say when we’ll see the 2012 1 Series, but a debut in Frankfurt later this year – likely alongside the all-new electric i3 – is a safe bet.
Electric Mobility and Hybrid Proliferation
As we already revealed, BMW’s i3 EV will have its motor mounted amidships and send power to the rear wheels, but that’s only half the story. The motor fitted to BMW’s first electric vehicle will output 125 kW (168 hp) and 184 lb-ft of torque, with the battery pack weighing a relatively scant 110 pounds. Rather than going for a one-size-fits-all approach for its batteries, BMW is developing different cells for different applications, ranging from mild hybrids to full EVs. For the i3, BMW is using scads of single, 3.7-volt cells arranged in groupings of between 250 and 400 volts, and when the production version arrives next year, it should have a range of around 100 miles.
On the hybrid front, the i8 plug-in hybrid flagship will come equipped with a turbocharged three-cylinder powering the rear wheels and two electric motors – one up front and another in the rear – to provide either a performance boost or all-electric motivation for an unspecified range.
The Future is Light(weight)
Like nearly every automaker on the planet, BMW is keen on reducing overall curb weight in the coming years, and its position as a premium automaker should help to alleviate some of the sticker shock that comes with the inclusion of exotic materials and compounds. BMW showed us a range of lightweight components that are either already in production or are slated to arrive in the next few years. Here are the highlights:
No exhibition of lightweight tech would be complete without everyone’s favorite fiber, and BMW has developed a carbon composite hood that’s not only lighter and stronger than its steel counterpart, but less expensive to produce. Weighing in at just over seven pounds dry (12 pounds with paint and clear coat), BMW’s carbon fiber hood is comprised of an outer weave, inner honeycomb structure and a finish that takes less than 30 minutes to apply. A comparable steel hood would weigh nearly 40 pounds, be considerably thicker (the carbon hood is 6 mm wide at its narrowest point) and still susceptible to corrosion. Additionally, the tooling to create the carbon hood is less than the steel variant and it deforms the same, allowing a body shop to use traditional resin composites to fix a dent or hole.
 A forged aluminum wheel is far from a heavy weight, but BMW wants to go further with a new hollow wheel design that saves over three pounds per corner and is injected with a silica foam to maintain stiffness and rigidity. |
Aluminum is beginning to find its way into more and more products from BMW, including a lightweight roof fitted to the 7 Series that saves over 11 pounds and aluminum skins on the current 5 Series saving some 50 pounds per door.
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Unsprung weight is the enemy of handling, and the majority of that unwanted mass is due to the massive discs and beefy calipers required to slow a two-ton sport sedan. To address this, BMW is working on a prototype “Slim Brake” system that has a larger diameter than a standard disc, but is hollow at the hub and allows more mass to be spinning further out, maintaining critical braking pressure. BMW estimates that this new design could save over 10 pounds on each front wheel (slightly less in the rear where the brakes are smaller), but would require the wheels to be sized at 19 inches or larger due to fitment issues.
