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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.

Nissan leaning on JATCO to remedy CVT problems

Nissan's decision to fit continuously variable transmissions across even more of its new models may be coming back to bite the Japanese automaker, as it's been hampered by customer satisfaction issues relating to its XTronic CVTs, which are provided by a supplier called JATCO.
From what we're understanding, the issue largely relates to customers' unfamiliarity with the non-traditional shift nature of a CVT. Dealers have reported complaints and service visits from owners over the belt-driven automatics (did these people not test drive the cars before they bought them and notice that they don't shift conventionally?).
The company, which Nissan owns 75 percent of, has come under fire from none other than Nissan CEO Carlos Ghosn, who's spoken about JATCO and its troubles rather openly. "Every time you launch a new CVT you always have some risks," Ghosn said in an interview with Automotive News. "So we now have a process by which, before we launch any new CVT, [JATCO] come before the Nissan executive committee to explain all the measures they have taken to make sure there are no surprises."

Automakers drop support for Trump effort against California emissions

WASHINGTON — Toyota, Fiat Chrysler (now known as Stellantis following its merger with Peugeot) and other major automakers said on Tuesday they were joining General Motors in abandoning support for former President Donald Trump's effort to bar California from setting its own zero emission vehicle rules. The automakers, which also included Hyundai, Kia, Mitsubishi, Mazda and Subaru, said in a joint statement they were withdrawing from an ongoing legal challenge to California's emission-setting powers, "in a gesture of good faith and to find a constructive path forward" with President Joe Biden. The automakers, along with the National Automobile Dealers Association, said they were aligned "with the Biden administrationÂ’s goals to achieve year-over-year improvements in fuel economy standards." Nissan in December withdrew from the challenge after GM's decision in November shocked the industry and won praise from Biden. On Monday, the Justice Department asked the U.S. Appeals Court for the District of Columbia to put the California emissions litigation on hold to "ensure due respect for the prerogative of the executive branch to reconsider the policy decisions of a prior administration." Biden has directed agencies to quickly reconsider TrumpÂ’s 2019 decision to revoke CaliforniaÂ’s authority to set its own auto tailpipe emissions standards and require rising numbers of zero-emission vehicles, as well as Trump's national fuel economy rollback. Asked to respond to the automakers' action, White House climate adviser Gina McCarthy said in a statement that "after four years of putting us in reverse, it is time to restart and build a sustainable future, grow domestic manufacturing, and deliver clean cars for America." California Governor Gavin Newsom praised the automakers on Twitter for "dropping your climate-denying, air-polluting, Trump-era lawsuit against CA" and urged them to join the voluntary framework. TALKS WITH BIDEN Separately, an industry trade group on Tuesday proposed to start talks with Biden on revised fuel economy standards that would be higher than Trump-era standards but lower than ones set during the prior Democratic administration. The Trump administration in March finalized a rollback of U.S. Corporate Average Fuel Economy standards to require 1.5% annual increases in efficiency through 2026, well below the 5% yearly boosts under the Obama administration rules it discarded.