1969 Chevelle Ss 396 4 Speed Barn Car on 2040-cars

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GM trucks get hybrid versions, but you'll probably never see one

A few years ago, General Motors sold hybrid versions of its Chevy Silverado and GMC Sierra pickups. They weren't very good, using GM's old two-mode hybrid system that resulted in only negligible fuel economy gains. But GM's trying again, launching eAssist models of the 2016 Silverado and Sierra that are said to offer 2-mpg improvements in city, highway, and combined fuel economy ratings. Problem is, you probably won't be able to get one. Only 700 eAssist trucks will be made for the 2016 model year – 500 Silverados and 200 Sierras. When you consider that GM moved 824,683 examples of its light-duty pickups in 2015, this small run represents 0.08-percent of all Silverado/Sierra production, and GM says it "will monitor the market closely ... and adjust as appropriate moving forward." But that's not the only limitation. The eAssist trucks will only be sold through California dealers. For the Silverado, eAssist can only be optioned on the 1500 Crew Cab 1LT 2WD model, and for the Sierra, the fuel-saving technology is solely available on the 1500 SLT Crew Cab 2WD model with the SLT Premium Plus package. Granted, in terms of the Sierra, that means you get niceties like LED headlights and taillights, Apple CarPlay and Android Auto, Bose premium audio, heated seats and steering wheel, lane keep assist, and more. In the trucks, eAssist combines a small electric motor and 0.45-kWh battery pack with the pickups' 5.3-liter V8. GM estimates total output of 355 horsepower and 383 pound-feet of torque – no more horsepower than the non-eAssist trucks, but three more pound-feet of torque. GM says the eAssist trucks can tow up to 9,400 pounds, and the battery only adds 100 pounds to the trucks' weight. The electric motor provides 13 hp and 44 lb-ft of torque for a boost of acceleration off the line, or during passing. It also allows the engine to run in four-cylinder mode for longer periods of time. eAssist uses regenerative braking to help power onboard electrical systems, and adds start/stop to the powertrain. Finally, the so-equipped trucks have a six-percent improvement in aerodynamics, thanks to a soft tonneau cover and active grille shutters in the front fascia. Great news is, the eAssist option is relatively inexpensive, only costing $500. But good luck getting your hands on one.

2015 Chevrolet Corvette Z06 Convertible is the track car for sun worshippers

Supercharged, 6.2-liter V8? Check. Seven-speed manual? Check. Obsession with weight? Check.
What did you expect when Chevrolet said it was bringing a new Corvette variant to the 2014 New York Auto Show? Maybe a sticker and trim package, like the C6 Corvette Grand Sport or a tie-in deal like the Black Widow car from Chicago? On the opposite end, maybe there was an even more hardcore Z06 waiting in the wings. Who knew?

'Killing a Duramax' Gale Banks YouTube series methodically tunes a diesel to death

Learning or perfecting a skill by watching YouTube videos is known as attending YouTube University. GM Authority picked up on one of the video site's more fascinating courses, hosted by Gale Banks; in a fair world, he should be referred to as Professor Banks when it comes to diesel engines and truck tuning. A few months after GM introduced the updated L5P 6.6-liter Duramax diesel V8 in the 2020 Chevrolet Silverado HD and GMC Sierra HD that ships with 454 horsepower and 910 pound-feet of torque, Banks decided he wanted to methodically tune the engine to death. The purpose of the resulting series, called "Killing a Duramax," is to push more power out of the engine in order to discover which parts break and when — or, as Banks puts it, force-feed the Duramax "until the crank hits the street and the heads hit the hood." With that knowledge, Banks can figure out all the weak points on his way to building what he calls a "Superturbo," that being a supercharged, twin-turbo race engine with more than 1,000 hp. What makes the series fascinating is Banks' knowledge, paired with the company's comprehensive iDash engine monitoring system that keeps tabs on a glut of parameters every step of the way. So for instance, you get Banks explaining the differences between inches of mercury and barometric pressure, how those are different from the water content of the air measured in grains, then showing those readouts on the iDash, then explaining in detail how they affect the air density in the Duramax system. The stock Borg-Warner variable turbo gets a lot of airtime — Banks accuses it of being "out to lunch" because he feels it's the weakest link on the engine. That turns into a turbo teardown and a deep explanation of performance pitfalls, such as when air pressure on the turbine begins to diverge from the boost pressure coming from the compressor. Banks says he can keep close tabs on where power's coming from, because the iDash monitors the horsepower contribution provided by the ambient air, the turbo, and the intercooler separately. The major changes so far are a stouter Precision 7675 turbo and TurboSmart wastegate (episode 5), a twin intake (episode 6), a custom liquid-cooled intercooler from a marine engine, a new GM oil cooler and synthetic oil (episode 10), and new injectors (episode 11).