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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.

Our favorite mid-engine Corvette theories and rumors

The mid-engine Corvette! We just saw blurry photos through the foliage, and are hearts are all aflutter because it means that this car is real. And it's the most " never before" Corvette since 1984. Which leads us to all kinds of wacky theories and speculation. Everybody knows something or heard from a guy. None of those guys (or gals) from GM are talking to Autoblog, to be clear. But that won't stop us from stirring the pot. Let's go over a few point-by-point. The pushrod engine will be replaced by an overhead-cam V8 Car and Driver has repeatedly reported that an overhead-cam engine will come after the mid-engine Corvette's debut with an old-school pushrod. We've heard the same thing firsthand, albeit from a source with no connection to the development of the Corvette or powertrain. "At some point two valves can't pass future emissions regulations," said the guy we know. While the pushrod engine is compact, the design makes it difficult - if not impossible - for sophisticated variable valve timing (and lift) systems that control combustion with more precision. Hasty conclusion: The pushrod engine has a finite life in front of it. This one's a lock, it's a just a matter of when. Bowling Green's new paint shop is really the mid-engine assembly line Credit to Reddit for this one. Like we said, everybody knows a guy. But let's look deeper. The new paint facility costs $439 million dollars and adds 450,000 square feet, almost half the size of the existing plant. Plus GM announced another $290 million in upgrades at Bowling Green Assembly. That sure sounds like a lot of money, but you can actually spend that much on a paint booth. Porsche spent 500 million Euros (about $561 million dollars) to add the Macan assembly to its Leipzig, Germany plant in 2014. Chrysler shelled out $850 million for a paint shop in Sterling Heights, Michigan. GM spent $600 million for a new paint shop at the Fairfax (Kansas City) plant. Honda, on the other hand, is working on a thrifty $210 million project in Marysville, Ohio that includes a 300,000 square foot expansion, and the low-volume Acura NSX facility only cost $70 million. Hasty conclusion: The square footage and cost could easily mean a new assembly line instead of (or in addition to) a paint line. And if the NSX plant was really that cheap, GM could have hidden a similar sum in its existing announcements.

Chevy Silverado Midnight Edition, Custom ready to stand out in pickup line

Chevrolet spent its Chicago Auto Show introducing a pair of fullsize pickups that promise image-conscious buyers a truck experience that goes beyond the standard range, with the murdered-out Midnight Edition and the um, not murdered-out, Custom. Let's start with the Custom, which adds 20-inch alloys, as well as chrome bumpers, mirror caps and door handles to the Silverado LS. Available in both V6 and V8 varieties, and with the customer's choice of two- or four-wheel drive, the Silverado Custom is the decidedly mellower example of Chevy's special edition styling. The Midnight Edition, meanwhile, throws subtlety out the window with a menacing set of visual upgrades. Based on the Z71, the Midnight adds 18-inch wheels, a spray-in bedliner and unique Z71 and Bowtie badges, all in black, of course. The front and rear bumpers, headlamp bezels, tow hooks, mirror caps and door handles, are also finished in the stealthy shade. Check out our live images of both special edition trucks, and let us know what you think down in Comments.