2003 Chevrolet Tahoe Z71 Sport Utility 4-door 5.3l 1 Owner Garaged Near Mint 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.

Chevy might've pulled out of NASCAR if it weren't for new Gen 6 car

We've been on the fence with NASCAR for some time now. On one hand, it's some of the closest racing anywhere in motorsports, with actual passing and door-handle-to-door-handle action as a matter of course. But on the other, it's become template racing - a personality-driven sport more about the drivers than any sort of loyalty to a particular automaker. The Car Of Tomorrow format really rammed that message home, with a racecar's identity coming down to little more than headlamp stickers slapped on the nose. That's not necessarily a bad thing in and of itself, but we've wondered for some time what's in it for the automakers, who pay big money to stay in a series that has had little increasingly little do with street car sales, let alone innovation.
Apparently General Motors was beginning to wonder the same thing. In a new ESPN report, Rick Hendrick, team owner of Hendrick Motorsports, suggests that GM would have seriously considered leaving NASCAR if it wasn't for the move away from the COT to the new Gen 6 racer. According to Hendrick, GM North America boss Mark Reuss spearheaded the charge away from the 2007 COT and toward a racecar with clearer automaker ties - cars like the new Chevrolet SS racer shown above. Learn more about the fight for a closer-to-production look in the ESPN story at the link.
Now, if we could just get more rear-wheel drive V8 coupes into showrooms....

AMC Trans Am Javelin SST, an ultra-rare underdog, is up for auction

Among the rarest of the American muscle cars that went racing in the early Seventies — cars including the Camaro Z/28 and the Boss 302 Mustang — the 1970 AMC Trans Am Javelin SST may be the most hard to find, and among the most valuable. Only 100 units of this unique Javelin were produced, and one of them is up for auction at the Mecum event in Dallas on September 20. The Trans Am Javelin was fashioned in a patriotic livery of tricolor paint — red, white and blue — and arrived after the American Motors Corporation had decided in 1968 to compete in the Trans Am racing series against Ford and General Motors. The company's chief driver, Mark Donohue, would dominate the 1971 season, taking seven wins in his Javelin AMX and that yearÂ’s SCCA Trans-Am Championship. AMC took the trophy with 82 points, well ahead of Ford's 61, Chevrolet's 17 and Pontiac's paltry 7. The example listed for auction came equipped with a 390-cubic-inch V-8 engine with 325 horsepower at 5,000 rpm and 420 pound-feet of torque, power steering and brakes, dual exhaust, BorgWarner four-speed manual transmission and Hurst competition shifter. Its “ram induction system” sealed a chamber around the air filter so that cool air from the functional hood scoop would be funneled into the intake. This JavÂ’s factory price was $3,995 — a mere $32,000 or so in today's money, though it was expensive by the standards of the time. The 100 Trans Ams were among 19,714 Javelin units built in 1970, so they started out rare, and today the surviving examples are highly collectible, if and when they come up for sale. No bid estimate is available yet. Related Video: Motorsports Chevrolet Ford Pontiac Auctions Automotive History Racing Vehicles Classics