2002 Nissan Xterra Xe on 2040-cars

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MotorWeek checks out two sides of the '90s Japanese car scene

MotorWeek's Retro Reviews let you feel nostalgic about a huge range of classic cars, and the latest two releases offer a look at two very different sides of the Japanese car market in the 1990s. The video above shows off tuned examples of the Mazda RX-7 and Nissan 300ZX. Check out the clip below to remember the 1997 Honda CR-V, if you want to reminisce about something a little more utilitarian. The RX-7 and 300ZX were among the era's best Japanese sports cars, and these examples' suspension and engine overhauls gave them an extra boost. Peter Farrel Supercars tunes the Mazda, and the vibrant yellow paint and body kit make it look ready for an episode of Initial D. The updated powertrain stands up to the mean styling and gets the RX-7 to 60 miles per hour in 4.5 seconds. The Stillen 300ZX GTZ sports a giant wing, and new turbos take the output to 465 hp. It sprints to 60 in 4.9 seconds. The CR-V sits on the opposite end of the automotive spectrum as the tuned RX-7 and 300ZX, but it's even more important in a historical sense. The Honda (along with the Toyota RAV4 and others) was among the progenitors of today's mega-popular compact crossovers. These early examples set the foundation for offering buyers a utilitarian vehicle in a comfortable package with good fuel economy at an affordable price. The CR-V had some quirky charm, too, like the removable picnic table hidden in the cargo floor. This content is hosted by a third party. To view it, please update your privacy preferences. Manage Settings.

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's autonomous cars could drive in US first, maybe by 2020

Future shock could be just six short years away, and coming first to the US. Nissan says it might start making autonomous versions of its cars available in the US by 2020, before the tech hits the road in other countries. The Japanese automaker is in extensive discussions with regulators from California, the best-selling state for the Leaf battery-electric vehicle, for allowing self-driving vehicles to be on its roads, Hybrid Cars says, citing a conversation with Nissan executive Andy Christensen at the recent Detroit Auto Show. Many decisions need to be made between now and then, given the hurdles related to issues such as regulations, liability, safety and technology - and Christensen said the first wave of self-driving vehicles would be able to do their thing only on the highway. The vehicle of choice is most likely to be the Leaf because it's completely battery operated, making the conversion to autonomy that much easier. Last summer, Nissan chief Carlos Ghosn first promised production autonomous cars by 2020. The automaker has teamed up with MIT, Stanford, Oxford and others to extensively test its "Autonomous Drive" concepts since then. Late last year, Nissan tested a self-driving Leaf on Japanese public roads. Nissan is not alone promoting autonomous driving as a way to increase safety, fuel economy and traffic flow, just some of the reasons why the idea may be the wave of the nearer-than-we-thought-future. For example, the company says 93 percent of accidents are caused by driver error.