2003 Infiniti M45 Base Sedan 4-door 4.5l on 2040-cars

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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.

2019 Infiniti QX50 starts fresh with a new face and trick engine

Last week, Infiniti rolled out the refresh of the big daddy QX80 in Dubai. At this year's Los Angeles Auto Show, the Japanese automaker is poised to reveal something that's bound to be far more mainstream: the 2019 Infiniti QX50 and its trick variable compression turbocharged engine, or VC-T. In addition to the new engine, the QX50 drops rear-wheel drive in favor of an all-new front-wheel-drive platform and gets the new ProPilot assist technology that debuted on the Nissan Leaf. The QX50 may be the headliner, but the engine is the really interesting bit. This 2.0-liter turbocharged inline-four can adjust the stroke of the pistons on the fly, varying the engine's compression from 8:1 to 14:1, and giving the new midsize crossover improved efficiency and diesel-like torque. It's rated at 268 horsepower and 280 pound-feet of torque, down 57 horses but up 14 pound-feet. Front-wheel-drive models hit 60 mph in 6.7 seconds. That drops to 6.2 seconds with all-wheel drive. Combined fuel economy is 27 mpg for front-wheel-drive QX50s and 26 mpg for all-wheel-drive variants, both up from the abysmal 20 mpg combined rating of the current model. Power is sent through a continuously variable transmission. If it's like other Nissan and Infiniti CVTs, it will be inoffensive if a bit lifeless. We've covered the details of this powertrain extensively already, but it's great to see companies giving more life to the internal combustion engine. The new platform marks a big improvement over the outgoing QX50 in terms of platform rigidity and space efficiency. Rear-wheel drive might be fun, but it's never ideal from a packaging perspective. Cargo capacity is up from 31.6 cubic-feet to 37 cubic-feet. With the seats down, the space expands to 60 cubic feet, up from 50.1 cubic feet. That's not exactly class-leading, but it's no longer among the class-worst. The 2019 QX50 will use a new type of high-tensile steel, improving torsional rigidity by 23 percent and shaving overall weight. The styling falls in line with most other Infiniti products. The outgoing model had a bit of an identity crisis, looking more like a lifted wagon than a fully-realized crossover (it was, after all, essentially a G35/G37 wagon). This new one has much more conventional SUV proportions. In fact, it looks like a 7/8-scale version of the new QX80 with a front-wheel-drive profile. That's either good news or bad news, depending on where your tastes fall.

Six luxury-car features I'm ashamed to admit I love

A hot compress felt wonderful on my sore back. The methodical kneading of my shoulder blades loosened the knots that formed over several hours of driving. The Swedish-style pulses firing into my lumbar region released more tension.
I wasn't getting a much-needed massage following a recent road trip. I was getting it during the road trip.
I grew up riding in the back seat of a 1976 Chevy Nova. But once you use these lux features, it's easy to go soft.