2003 Gmc Sierra 2500 K2500 Heavy Duty on 2040-cars

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.

Supercharged 2015 GMC Yukon Denali sounds evil, runs 0-60 in 4.5 seconds

Speeding along in a sports car is undoubtedly a ton of fun, but some owners need the ability to carry a lot of people and their stuff and don't want to sacrifice the ability to put the power down. The tuners over at Hennessey have that demographic covered with their growling, supercharged power kits for the GMC Yukon Denali. The upgrades come in three forms for the SUV's 6.2-liter V8: HPE550 with 557 horsepower, HPE600 with 605 hp and HPE650 with 665 hp. This video showcases the full-bore version, and this Denali can definitely hustle in a straight line. The power bump comes courtesy of a 2.9-liter supercharger, intercooler and high-flow cylinder heads to add over 200 horsepower compared to stock, and the final result is a bellowing SUV that rears up off he line to throw the driver back into the seat. The sprint to 60 miles per hour lasts just 4.5 seconds. Check out this hasty hauler in action in the video above.

Driving the Panamera and Mike's Rant | Autoblog Podcast #487

This week we cover some recent news like the upcoming Land Rover Discovery, updates to FCA's large car platform (including the Challenger), and talk about water injection. Then we go into what we've been driving - David just finished his time in the Porsche Panamera Turbo and Mike tried the GMC Acadia. And then Mike (who is still uncomfortable writing in the third person) goes on a rant about why automakers shouldn't specify which cars are aimed at women. The rundown is below. Remember, if you have a car-related question you'd like us to answer or you want questionable buying advice, send a message or a voice memo to podcast at autoblog dot com. Autoblog Podcast #487 The video meant to be presented here is no longer available. Sorry for the inconvenience. Topics and stories we mention Land Rover is bringing a new Discovery to the Paris Motor Show An AWD Challenger is coming, which means more Hellcat The Jeep Wrangler finally gets modern headlights Water Injection from the BMW M4 GTS is coming to the mass market 2017 GMC Acadia 2017 Porsche Panamera Turbo A rant about sexism in marketing Another take on the $6000 fun car Rundown Intro - 00:00 The news - 00:50 What we've been driving - 11:30 Rant - 30:49 Listener's fun car - 35:56 Total Duration: 42:22 Get The Podcast iTunes – Subscribe to the Autoblog Podcast in iTunes RSS – Add the Autoblog Podcast feed to your RSS aggregator MP3 – Download the MP3 directly Feedback Email – Podcast at Autoblog dot com Review the show in iTunes