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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.

General Motors Recalls Nearly 780,000 Cars To Fix Deadly Problem

General Motors is recalling nearly 780,000 compact cars in North America because the engines can shut down unexpectedly and cause crashes. The company says six people have been killed in crashes related to the problem. The recall affects Chevrolet Cobalts and Pontiac G5s from the 2005 through 2007 model years. U.S. safety regulators say the weight of the key ring and rough roads can move the ignition switch out of the run position, cutting the engine and electricity. If that happens, air bags may not work. GM says there have been 22 crashes from the problem. All happened at high speeds. Dealers will replace the ignition switch for free. GM says owners should remove nonessential items from key rings until the problem is fixed. Related Gallery Chevy Impala Earns Highest Accolades From Consumer Reports Recalls Chevrolet GM Pontiac Cobalt

2014 Chevrolet C7 Corvette wastes no time zooming into Jay Leno's Garage

Where else would you expect the 2014 Chevrolet Corvette Stingray to show up first? Although this time it isn't exactly in Jay Leno's Garage, Leno instead playing an away game at Brown's Classic Auto in Scottsdale, Arizona. Nor does Leno drive the car, instead taking an 11-minute walkaround of the new American sports car with General Motors design head Ed Welburn, the same man who recently brought by a string of classic Corvettes to the talk show host's California compound.
It is, admittedly, a love-fest for the American sports car now featuring 450 horsepower and 450 pound-feet of torque, but one that also features admissions about previous Corvette seats like "they were kinda rough," and the explanation that labeling the coupe "Stingray" means not having to call it "the base Corvette." On top of that, Welburn also explains the proper application of the term "dashboard." You can watch it all in the video below.