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Infiniti's new VC-T changes the rules of small turbocharged engines

The upcoming Infiniti QX50 crossover does not get our pulse racing, no matter how shapely the QX Sport Inspiration concept that previews it may be. No midsize SUV does, to be fair. But it has something special under the hood – the world's first production variable-compression-ratio engine. That means the QX50's 2.0-liter turbo four, which makes 268 horsepower and 288 pound-feet of torque, will have up to 27 percent better fuel economy. Here's how it works. The trend of moving to smaller, turbocharged engines carries with it one big falsehood. Under low load when the turbo isn't needed, these engines are less efficient than an equivalent engine without a turbo because of the low compression ratio the turbo requires. That is, if you never need the extra power, you're wasting fuel. Turbocharged (and supercharged) engines use a lower compression ratio to prevent detonation. When you force extra air in a cylinder and mix it with fuel, it's more likely to prematurely go boom. Lowering the compression ratio prevents this problem, but it's less efficient. Infiniti's VC-T promises the best of both worlds, with a compression ratio that ranges from 8.0:1 for high-power turbo needs to a 14.0:1 ratio for fuel-sipping efficiency. At its heart the VC-T engine is a simple idea, but it's complicated to explain. Consider yourself warned. The photo below from Infiniti serves as a good visual overview. For the truly nerdy, this patent application covers the mechanical concept. Instead of having the pistons connected to the crankshaft, Infiniti's engine has a pivot arm with a connection on each end. One end connects to the piston, the other connects to a second lower shaft, which is controlled by an actuator arm. At any given time the engine's pistons move up and down according to the lobes on the crankshaft. But the actuator arm can change the angle of the pivot arm up and down. That is, the pistons still move in the same motion with the same stroke, but phase the entire stroke up or down. Move the pivot up and there's less room at the top, which means a higher compression ratio. Move the pivot down and the compression ratio goes down, too. As an added bonus, the lower shaft eliminates the need for counter-rotating balance shafts. Infiniti says this system works constantly and can vary the compression ratio to any number between 8:1 and 14:1. It also uses electronic variable valve timing on the intake valves to switch into Atkinson-cycle combustion for greater efficiency.

2014 Nissan Pathfinder Hybrid arrives with supercharged engine, 26 mpg combined

Nissan just launched the fully redesigned Pathfinder for the 2013 model year, and now, there's a fuel-sipping hybrid version making its debut here at the New York Auto Show. The 2014 Pathfinder Hybrid packs all of the same features found in the standard crossover, but offers slightly better fuel economy and an improved cruising range, to boot.
The new hybrid is powered by a 2.5-liter supercharged engine (we're assuming it's a four-cylinder, though Nissan hasn't specified) coupled with a lithium-ion battery and 15-kilowatt electric motor, capable of producing 250 horsepower and 243 pound-feet of torque - 10 less horsepower but three more pound-feet than the standard V6 Pathfinder. Nissan says the hybrid crossover will be rated at 25/27 miles per gallon (city/highway), with a 26-mpg combined rating. This means that on a full tank, the cruising range of the Pathfinder Hybrid is a cool 526 miles.
What's cool about the hybrid packaging is that Nissan has managed not to have it interfere with any of the interior functionality - the Pathfinder Hybrid still packs just as much cargo and passenger space as its naturally aspirated sibling. Official pricing has not been announced, but Nissan expects the hybrid to command an additional $3,000 over the standard model.

Ford F-150, Chevy Silverado, Toyota Tundra flunk IIHS headlight test

The Insurance Institute for Highway Safety put pickup truck headlights to the test and found that the majority of them were equipped with subpar units. The 2017 Honda Ridgeline was the only truck to earn a rating of "good." The large pickup truck test was comprised of the: 2016 to 2017 GMC Sierra, 2017 Nissan Titan, 2016 Ram 1500, 2016 to 2017 Chevrolet Silverado, 2016 to 2017 Ford F-150, and 2016 to 2017 Toyota Tundra. The Sierra's headlights earned a rating of "acceptable," the headlights found on the Titan and Ram 1500 were found to be "marginal," and the ones on the Silverado, F-150, and Tundra were rated as "poor." IIHS claims the F-150 was the most disappointing out of the large pickup trucks as both its halogen and optional LED headlights failed to provide adequate visibility during testing. The Ridgeline (which earned a "good rating"), is usually considered a midsize or small truck, though IIHS included it in the field of large pickups. The headlights on the 2016 Chevrolet Colorado, 2016 GMC Canyon, 2016 Nissan Frontier, and 2016 to 2017 Toyota Tacoma, which made up the small pickup truck group, all earned a rating of "poor." The IIHS claimed the Colorado had the worst headlights of any truck that was tested, as the base vehicle's units were only able to illuminate up to 123 feet in front of the car. The Ridgeline's headlights, for reference, were able to illuminate up to 358 feet in front of the vehicle. To conduct its test, the IIHS utilizes a special tool to measure how far light is projected out of the headlights in different driving situations. The trucks' headlights were tested in a straight line and in corners, while vehicles with high-beam assist were given extra praise. The headlights on the pickup trucks also mimic the testing that was done on small SUVs and cars earlier this year. Next year, automakers will need to fit their vehicles with headlights that earn a rating of either good or acceptable to earn the IIHS Top Safety Pick+. Related Video: