2008 Chevrolet Corvette

You've probably noticed that a horsepower war has been raging throughout the automotive spectrum, much to the chagrin of the Greens-we even have 438-horse hybrids ferpetesake. Naturally, the fighting is most intense among flagship sports cars, but thanks to a Reaganesque trickle-down effect (powernomics?), lesser models benefit, too. For example, after the engineers finished shoveling horsepower and torque into the engine room of the Corvette Z06 last year, there was enough left over to boost the lesser Corvettes, which will doubtless lead to further energizing of some other GM performance models as well.

We've analyzed the new LS3's myriad engine refinements in previous stories, so let's get right to the task of quantifying these improvements by turning the new Corvette loose on an empty stretch of Milford Proving Ground tarmac.

Our test car was a fully broken-in (1275 miles) early-production Z51 coupe, equipped with the NPP dual-mode performance exhaust, which reduces back-pressure by a whopping 80 percent at high engine speeds, adding six peak horsepower and four pound-feet, bringing the totals to 436 and 428, respectively. Naturally, we opted for the revised Tremec six-speed manual transaxle creating what is now the second best performance Corvette. Gearing in the Z51 is nine to 14 percent shorter in the first four gears relative to the base manual, and while the base six-speed paddle-shifted automatic matches the Z51's gearing in first, the other gears are 12 to 25 percent taller. Automatic buyers can opt for a slightly shorter axle ratio (2.73:1 versus 2.56:1), which doesn't have much effect on the performance numbers, but improves in-gear passing acceleration. GM reckons the automatics should trail our Z51 stick by about a tenth to 60 mph, two-tenths and two mph in the quarter. We wheedled and cajoled for a chance to verify these projections using our photo car, but because it was so green (300 miles), GM said no dice.

Relatively short gearing makes it easy to generate smoky burnouts for the camera, but commands judicious throttle input to achieve the optimal hole-shot. For the first few runs, a 2000-2500-rev clutch drop generated minimal wheelspin with the tires hooked up at around 3500 revs. Because the LS3 is churning out (only) around 250 horses at that point, better results are obtained by launching the LS3 with another 1000 revs (3000-3500) and feathering the throttle to hook up at more like 4200 rpm, when 350 thoroughbreds are pulling hard. That approach paid off with a blistering 4.1-second dash to 60 mph en route to a 12.5-second, 115.0-mph quarter mile. Those figures line up almost perfectly with those of our best 2002 C5-generation Z06. No surprise, really-that car made, ahem, "only" 405 horsepower and 400 pound-feet of torque.