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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.

IIHS: High numbers of drivers treat partially automated cars as fully self-driving

WASHINGTON — Drivers using advanced driver assistance systems like Tesla Autopilot or General Motors Super Cruise often treat their vehicles as fully self-driving despite warnings, a new study has found. The Insurance Institute for Highway Safety (IIHS), an industry funded group that prods automakers to make safer vehicles, said on Tuesday a survey found regular users of Super Cruise, Nissan/Infiniti ProPILOT Assist and Tesla Autopilot "said they were more likely to perform non-driving-related activities like eating or texting while using their partial automation systems than while driving unassisted." The IIHS study of 600 active users found 53% of Super Cruise, 42% of Autopilot and 12% of ProPILOT Assist owners "said that they were comfortable treating their vehicles as fully self-driving." About 40% of users of Autopilot and Super Cruise — two systems with lockout features for failing to pay attention — reported systems had at some point switched off while they were driving and would not reactivate. "The big-picture message here is that the early adopters of these systems still have a poor understanding of the technologyÂ’s limits," said IIHS President David Harkey. The study comes as the National Highway Traffic Safety Administration (NHTSA) is scrutinizing Autopilot crashes. Since 2016, the NHTSA has opened 37 special investigations involving 18 deaths in crashes involving Tesla vehicles and where systems like Autopilot were suspected of use. Tesla did not respond to requests for comment. Tesla says Autopilot does not make vehicles autonomous and is intended for use with a fully attentive driver who is prepared to take over. GM, which in August said owners could use Super Cruise on 400,000 miles (643,740 km) of North American roads and plans to offer Super Cruise on 22 models by the end of 2023, did not immediately comment. IIHS said advertisements for Super Cruise focus on hands-free capabilities while Autopilot evokes the name used in passenger airplanes and "implies TeslaÂ’s system is more capable than it really is." IIHS in contrast noted ProPILOT Assist "suggests that itÂ’s an assistance feature, rather than a replacement for the driver." NHTSA and automakers say none of the systems make vehicles autonomous. Nissan said its name "is clearly communicating ProPILOT Assist as a system to aid the driver, and it requires hands-on operation.

Ken Block's Gymkhana 8 to feature Dubai Police cars?

Yesterday we showed you the shiny Ford Fiesta that Ken Block will slide, spin, and hoon through the next Gymkhana video. In case the image above isn't clear, that video will drop at midnight EST on February 30th on the Ford Performance YouTube channel. We don't know all the entire premise of the video yet, but this Tweet from the man himself reveals that the video will be set in Dubai. Block is standing on the Fiesta we saw yesterday, and arrayed behind him are a handful of those famous Dubai Police cars you're probably familiar with. The force has a fleet of sportscars and supercars, and the purpose is outreach and goodwill among its citizenry, not necessarily the pursuit of criminals. This content is hosted by a third party. To view it, please update your privacy preferences. Manage Settings. From left to right, we can see a Maserati GranTurismo, Porsche 911, what looks to be a Nissan GT-R obscured by Block's Fiesta, a McLaren (likely a 650S), Ford Mustang, and a Ferrari 599 of some ilk. Will they take part? Maybe Block will try and run from what might be the most horsepower-intensive police fleet in the world. We'll have answers (and a few minutes of pure Block hooniganism) in a few days. Related Video: