2007 Infiniti M45 Sport 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.

2016 Infiniti QX50 is new and improved, kind of [w/video]

The Infiniti QX50 is, to be frank, ancient. It hit the market way back in 2007, and has labored on ever since. Through December of last year, the company only moved 2,727 QX50s. The year before, there were only 2,164 sales, and 3,495 in 2012. What do all three years have in common? The QX50 was Infiniti's slowest seller in each of them. Here's hoping, then, that this latest update will boost the 2+2 crossover's appeal. Being shown today at the 2015 New York International Auto Show, Infiniti has made a number of updates to its smallest crossover, with the most notable being a 3.2-inch stretch in its wheelbase and a 4.5-inch increase in its overall length. That makes for an enormous 4.3-inch increase in the legroom of the formerly cramped second row. Infiniti also made slight increases to the overall ride height, of 0.4 inches in for rear-drivers and 0.8 inches for all-wheel-drive variants. Outside of the dimensional changes, Infiniti also beefed up the former EX37's exterior, with new front and rear bumpers that boast SUV-like scuff plating, as well as LED accents in the new headlights and a new grille that is more in keeping with the brand's current design language. LED taillights sit out back as standard, while Infiniti will happily sell consumers an optional xenon headlight package. Infiniti may have updated the exterior, but the cabin looks largely unchanged, aside from the extra space in the second row. It looks like a complete carryover in terms of features, trim and general layout. Also unchanged is the QX50's 3.7-liter V6 engine. Output remains fixed at 325 ponies and 267 pound-feet of torque. Regardless of whether power goes to the rear or to all four wheels, a seven-speed automatic is in charge of managing the power. We'll have more on the freshened QX50, including live images, coming soon from the floor of the 2015 New York Auto Show.

2025 Infiniti QX60 ditches V6, gains VC-turbo

The 2025 Infiniti QX60 will ditch its long-running VQ-series V6 in favor of Infiniti's variable-compression turbo engine. There's news beyond the powertrain overhaul too as the 2025 model sees some equipment upgrades and a new Black Edition. The blackout package is not new to Infiniti, but it's a first for this QX60. Let's start under the hood.  With 268 horsepower and 286 pound-feet of torque, the VC-T four-cylinder gives up 22 horses in exchange for 16 lb-ft of torque. That's a bit of a side-grade rather than an upgrade, perhaps, but the new four-cylinder delivers better fuel economy, making the whole pill a bit easier to swallow. The FWD model will return 22 mpg city, 28 mpg highway and 24 mpg combined, the EPA says (vs. 21/26/23 with the V6) while the AWD model improves to 22 mpg city, 27 mpg highway and 24 mpg combined (from 20/25/22). That's a 10% bump in city mileage vs. the V6 — not earth-shattering, but not bad, either. And we know what you're thinking, but fear not; this doesn't mean the QX60 is now saddled with a CVT. The nine-speed auto carries over and yes, it can still pull 6,000 pounds with AWD and the tow package.  For 2025, all QX60s get a new fob with an optional automatic lock/unlock feature. The Black Edition (see the gallery above) will be available on Luxe models and includes the gloss black wheels, grille surround, roof rails and exterior badges; illuminated front and rear kickplates; "radiant" grille badge; welcome lighting and a black headliner. The base price of the Pure model is up just $550 from 2024, however the FWD variant of the Autograph has been dropped, making it $4,300 more expensive to get into the trim. However, the AWD variant only increases by $50. Here's pricing information for the entire 2025 QX60 lineup with front-wheel drive (including destination). AWD is $2,000 more on every trim but the Autograph, which bakes it in as standard equipment for 2025.  Pure: $51,550 Luxe: $58,150 Sensory: $60,450 Autograph: $67,500 Related Video:  2023 Nissan Pathfinder Rock Creek walkaround This content is hosted by a third party. To view it, please update your privacy preferences. Manage Settings.