Chevrolet Suburban 2500 4x4 Lt on 2040-cars

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Chevy's 6.6-liter Duramax is pretty much all new

To say there's a heated battle in heavy-duty pickups is an understatement, with Chevrolet, Ford, and Ram constantly trading blows of increased torque, horsepower, and towing capacity. The latest salvo is the revised, more powerful turbo diesel 6.6-liter Duramax V8 in the 2017 Chevy Silverado. It has 910 pound-feet of torque, an increase of 145, putting it nearly level with the Ford Super Duty. Here's a closer look at where those gains come from. How exactly did Chevrolet add all that torque plus 48 horsepower? The automaker essentially took a fine-tooth comb to the entire engine. Chevy says it changed 90 percent of the V8, and the cumulative effect of those small changes adds up to big increases. As you might guess, the turbocharger is updated. The larger unit features electric actuation of the variable nozzle turbine (VNT), and what Chevy calls a double axle cartridge mechanism that separates the VNT moving parts from the housing. That helps with heat performance as well, with a claim that the exhaust side of the turbo can run continuously up to 1,436 degrees Fahrenheit. Helping that cause are six exhaust gaskets made of Inconel - an nickel alloy that contains chromium and iron – and upgraded stainless steel for the exhaust manifold. Despite having the same cast iron cylinder block, albeit with some minor enhancements, the engine has new cylinder heads, pistons, piston pins, connecting rods, and crankshaft, which have all been upgraded to handle 20 percent higher cylinder pressures. Alongside the increase in pressure, Chevrolet also increased the cylinder head's structure with a honeycomb design. The pattern features high-strength aluminum with dual layer water jackets that not only improve strength, but also optimize water flow for better cooling. For 2017, the cylinder head also benefits from integrated plenum that aids the engine in getting more air under heavy loads. The cylinder head isn't the only component to get a minor update, as the pistons have a larger diameter pin for improved oil flow. The same detailed improvements has been bestowed to the humble connecting rods (second in our hearts only to the inanimate carbon rod). The new design has the bolts oriented roughly 45-degrees to the rod instead of parallel. The angle split design, as it's called allows for easier passage through the cylinder.

Callaway debuts its new C7 Stingray at National Corvette Museum

Callaway showed off its first tuned version of the 2014 Corvette Stingray at the National Corvette Museum last week, giving the rampant enthusiasts of America's sports car a look at the roughly 620-horsepower, supercharged rocket.
Unlike the Corvette SC610 we showed you back in January, this Stingray packs a fair bit more oomph. Horsepower is only up ten ponies, but torque has jumped from 556 pound-feet to "at least" 600 pound-feet. Neither horsepower nor torque is official quite yet, although Callaway is expecting to know just what its creation can do once testing and validation is completed later this month.
The 6.2-liter, supercharged V8 now boasts a new, three-element intercooler, which Callaway claims only allowed the inlet air temperature to increase by ten degrees Fahrenheit during dyno runs. Previous designs saw a 35-degree-Fahrenheit jump. The exhaust system has also been fettled with, and now is even less restrictive.

2014 Chevrolet Impala [w/video]

Can A Fleet Queen Become a Fullsize King?
On paper, the Chevrolet Impala is a pretty strong seller, posting annual sales that have hovered right around 170,000 units for the last two years, but it only takes one trip to practically any rental car agency to discover where the majority of those sales have come from. In fact, General Motors told Autoblog that a full 70 percent of Impala sales last year went to fleet companies for things like rental cars and government vehicles. Logic tells us that this is neither good for resale values nor name equity, so Chevrolet is getting ready to roll out an all-new Impala with improved comfort, styling and technology, hoping to turn the tables on its retail-to-fleet ratio.
Chevrolet's sedans have come on quite strong in the last few months with the introduction of the Cruze diesel and the SS sedan, but while these will likely be low-volume sellers, there's more pressure for the new Impala to perform well as GM looks to slash fleet sales and compete with the wide variety of full-size sub-luxury sedans. Riding on a platform shared with the Buick LaCrosse and Cadillac XTS, the 2014 Impala will compete against the Hyundai Azera, Ford Taurus and Toyota Avalon on the more traditional side, while also looking to take a bite out of somewhat sportier models like the Chrysler 300/Dodge Charger twins and the Nissan Maxima. We headed to sunny San Diego to see if this totally new Impala can stand on its own without the assistance of fleet companies and rental agencies. [w/video