Auto blog

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.

Cadillac CT6 production ceases January 2020 as part of D-Ham layoffs

General Motors filed paperwork under the Worker Adjustment and Retraining Notification Act with Michigan's Department of Labor and Economic Opportunity this week, detailing events to come at the automaker's Detroit-Hamtramck Assembly Plant. Starting February 28, 814 salaried and hourly workers at D-Ham, as its called, will be laid off. The 753 workers represented by the UAW will begin receiving offers in January to relocate to facilities in Michigan and Ohio, or buyout offers. As the 4-million-square-foot plant winds down through April 3 to a skeleton crew, the Cadillac CT6 ceases production in January 2020, and the last Chevrolet Impala comes off the line on February 28. The loss of the CT6 represents the end of Cadillac's latest brief, and highly regarded, adventure into flagship sedans. It might also mean the end of the 4.2-liter Blackwing twin-turbo V8 engine, at least for the moment. Both casualties are calamities. The death of the Impala closes the door on a nameplate in production for 52 years since 1957, having started off as a top-tier trim for the 1958 Bel Air known as the Bel Air Impala, once advertised with the line, "Lets you know you're the boss." As part of the new four-year labor agreement with the UAW, GM is keeping D-Ham open to build a new line of battery-electric vehicles, ultimately investing $3 billion and tripling employment to 2,225 workers when fully operational. The agreement described the coming EV as a "van" that would commence production in late 2021, but various reports say what's actually coming is a range of premium EVs in pickup and SUV bodystyles under the program codename BT1. The easy predictions put an electric GMC Sierra and Cadillac Escalade among the EV fold, but not until 2023, according to auto industry forecaster LMC Automotive. Before that, LMC claims an electric van will debut in late 2021, along with a battery-powered rebirth of the Hummer brand in pickup and SUV forms, also in late 2021. 

2015 Chevrolet Corvette Z06 [w/videos]

I think I was supposed to be back hours ago. Driving northwest on State Road 190 with a final destination deep in the heart of the Death Valley National Park, it occurs to me that I might have agreed to return after an hour or so, instead of the four I'll end up stealing, solo, in the new Z06. Somewhere in the combination of mountain vistas, arching, speed-hungry desert roads, and the sound of this titanic engine on a constant run up the rev ladder, I forgot everything I'd promised back at home base. The generous, civilized part of me worries for a moment that absconding with the new-best Corvette might have left one of my fellow journalists without a car. But the selfish part of me – the part largely in control of the rocket-launcher of a throttle under my right foot ­– says "screw it." I spent two days with the 2015 Chevy Corvette Z06, a monster of a sports car that will soon be dominating track days everywhere, and I never once was inclined to share it. Hurtling through the shattered stillness of the desert and pulling big Gs at Spring Mountain circuit, I never felt overly disposed to give up my seat. This Corvette, more than any I've yet driven, was deep enough to hold my attention; for two days, for two years, probably. With this Z06, the Corvette steps over the amazing-for-the-price category, and solidly into the best-cars-in-the-world zone. There are peripheral elements that remind me of its blue collar, Bowtie heritage, sure, but there's more that simply begs me to carry on driving... faster. Most casual car observers will be able to pick the 2015 Z06 out from its less aggressive Stingray brothers. Subtler hints include a new, more open grille, larger extractor on the taller hood and rather discreet badges on the flanks of the car. More outrageous is the finned spoiler on the rear trunk lid, and the widebody look offered from flared fenders – an extra 1.57 inches (40 millimeters) at their beefiest point. Even driving around performance-car-laden Pahrump, NV – loaded thanks to the very active community at the Spring Mountain racing resort – members of the local populace were turning heads, waving and generally noting the Z06 with approval when I drove through town. In Torch Red over black painted aluminum wheels, staggered at 19-inches in front and 20 at the back, the amped-up Z06 hits a new level of road presence for the C7.