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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.

Weekly Recap: BMW rolls out ambitious plug-in hybrid electric plan

"We believe that for the United States, this is going to be very important." – Julian Arguelles Let there be no doubt, BMW is serious about electric vehicles. The German automaker said this week it will make plug-in hybrid versions of all of its core models, an aggressive move that demonstrates its commitment to electric propulsion systems. BMW did not specify which vehicles will get the plug-in systems or provide a timeline for when they will arrive. But the announcement is clearly more than blustering, and the company revealed a 3 Series plug-in prototype this week at an event in France. BMW said the 3 Series uses a version of its 2.0-liter turbocharged four-cylinder engine (240 horsepower, 300 pound feet of torque) with an electric motor sandwiched between the engine and transmission in place of the torque converter. It has an all-electric range of 22 miles. A plug-in X5 with the same powertrain was also displayed alongside the 3 Series, though the X5 has been on the auto-show circuit for more than a year, including a recent stop in Los Angeles. Those two vehicles use "eDrive," and BMW's plans represent the first widespread transfer of its technology from development of the i3 and i8 models to more mainstream products. BMW said it's developing electric powertrains so they can be deployed rapidly across its range, and they are flexible enough to be used with fuel cells in future products. Enticingly, BMW is also working on a "Power eDrive" system, which debuted in a 5 Series GT concept at the event in France. This setup has two electric motors powered by a 20-kilowatt-hour battery pack, and when teamed with a four-cylinder turbo, pump out about 670 hp. Reinforcing BMW's commitment, the company will add more than 200 jobs at its factory in Dingolfing, Germany, to support electric-vehicle development. The moves come as BMW and other automakers diversify their portfolios while fuel economy and emissions regulations are getting tighter around the world. The United States has set a 54.5-mpg CAFE requirement for the 2025 model year. BMW said the electric vehicles were developed with an eye toward the US market, its government policies and its wide-ranging commuting styles. "We believe that for the United States, this is going to be very important," spokesman Julian Arguelles said. Ben Scott, a senior analyst in London with automotive research firm IHS, said BMW's moves are expensive – but necessary – to keep pace with the market.

Can Fernando Alonso win Indy? Here's why and why maybe not

SPEEDWAY, IN – The month of May has been a joy ride for Fernando Alonso at Indianapolis Motor Speedway. The two-time Formula 1 champion came to Indy having never turned left in a race car without also turning right. But he acquired such a feel for Indy's 2 1/2 -mile rectangle during a month of practice and qualifying that he's considered a strong contender to win the 101st Indianapolis 500 on Sunday, rookie or not. "You're not trying to bring somebody on who has very little experience driving very high-performance cars," said 2003 Indy 500 winner Gil deFerran, who this month has helped Alonso learn the nuances that make the speedway such a tough place to conquer. "I suppose it would be a little bit different if you were dealing with a younger, much less experienced person." Driving a McLaren Honda from the potent Andretti Autosport team, Alonso was consistently near the top of the speed charts in practice, he qualified fifth fastest at 231.300 mph, and he handled runs in heavy traffic like a driver who'd done it many times before. But those were the prelims. The race is another creature. "The car felt the best (it has) in the last two weeks. I was making some moves, taking some different lines. I am extremely happy." Other drivers say the speedway looks different on race day when the crowd, expected to top 300,000, fills the grandstands and makes an already narrow track seem even tighter. The three-wide rolling start is something Alonso has never experienced, and he will see the green flag from the middle of the second row between Takuma Sato and J.R. Hildebrand. And the space he'll be given by his competitors in the first 180 laps may disappear In the last 20 when it's every driver for themselves. Can a rookie like Alonso win this race? Absolutely, as Andretti driver Alexander Rossi showed last year when his team used a fuel-mileage strategy to win in his first taste of Indy. We're talking about Fernando Alonso here, who easily could show his rookie stripes to the rest of the field most of the day. His best lap in Friday's final practice, 226.608, was fifth fastest in the field and, more important, he said the car felt comfortable in heavy traffic. "The car felt the best (it has) in the last two weeks," Alonso said. "I was making some moves, taking some different lines.