Review: 2010 Chevrolet Corvette Grand Sport Convertible is just right

While Ford has been introducing a countless string of Mustangs that appeal to nearly every enthusiast on the planet, Chevrolet has had to make due with only three versions of the Corvette (five if you count both coupes and convertibles). Well, for 2010, Chevrolet is adding a new model to the mix, the Corvette Grand Sport. Bridging the gap between the base Corvette and the track-focused Z06, the Grand Sport – unlike the aluminum chassis Z06 and ZR1 – is available in both coupe and convertible form, giving 'Vette lovers another way to enjoy motoring al fresco.

After spending a few hours at General Motors' Milford Proving Grounds wringing out the GS on track back in August, we finally managed to snag some significant street time in a Crystal Red Grand Sport convertible. Lo and behold, when we looked inside we found a manual transmission, meaning this particular Grand Sport is packing the new-for-2010 launch control system. So now it's time to find out if this newest 'Vette variant is as livable on the road as it is fun on the track.

There's no mistaking the Grand Sport for anything but a Corvette. The long hood, arching fenders and bulging wheel wells show a lineage that goes back to the late C1 models of the early Sixties. Adding to the classic lines of the stock C6, the Grand Sport receives the front fascia, hood and fenders from the Z06. Everything is supported by the surprisingly strong hydro-formed steel structure, including the rear fenders, which are unique to the Grand Sport as the Z06 isn't available in a convertible and the track rat's rear arches won't fit.



Like all recent Corvettes, the 19-inch rear wheels are an inch larger than the fronts, while the slim, five-spoke design is unique to the GS. Rather than rolling on the standard painted wheels, our tester came equipped with the chromed versions, which are a bit too bling for our tastes. Thankfully, there's a third option: a sinister set of dark gray competitions wheels inspired by the C6.R. Yes, please.

On the topic of tires and wheels, while we expect most Corvette owners to hand-wash their rides, sometimes you just don't have the time or inclination. Unfortunately, the 12-inch wide, P325/30ZR19 Eagle F1 Supercar run-flats mounted on the rear simply don't fit through the guide tracks of most automatic car washes. In a vain attempt to run the GS through our local auto-wash to prep it for a photo shoot and check for leaks, the 275 mm front rubber barely fit, so we backed out and gave it a proper bath at home.



Fortunately, there wasn't much grime to hose off as the weather cooperated during most of our time with the Grand Sport. That also meant the top was dropped whenever we were behind the wheel. Lowering the roof is as easy as twisting the large single latch at the center of the windshield and then holding the switch to the left of the steering column. The power mechanism handles the rest, lifting the hard tonneau and stowing the lid underneath. Unlike a handful of modern convertibles, the Vette's top can't be raised or lowered while in motion, so when the sky finally opened, we made a mad dash to the side of the road to close up the fun.

While the Corvette isn't a particularly quiet car under the best of circumstances, the convertible doesn't seem to be appreciably louder than the coupe. Noise levels seem to be in check whether puttering around town or hitting the highway at speed, but when it comes to noise, one suggestion: check off the dual-mode exhaust on the option list. If you're going to drop the coin on something with a large displacement V8, you need to be able to enjoy it, and when the Grand Sport's rev counter sweeps past 4,000 RPM, a bypass valve opens up and... BAM! You're back in 1967.



The Grand Sport's interior is pretty much standard issue Corvette, from the base model to ZR1, it's essentially the same. Our convertible tester had the optional premium equipment group which tacks nearly $10,000 onto the price tag and brings with it a two-tone leather covering for the dash and door panels, memory seats, power telescoping steering column and the heads-up display, among a raft of other options. For a vehicle that can gobble up pavement at such a prodigious rate, the HUD is a major plus, allowing the driver to keep his eyes on the road while diving deep into corners. It's also customizable, offering a number of different information pages, including our favorite: a simulated analog tachometer with a digital speedo and lateral acceleration bar graph.

In the past, we've complained about the weak lateral and thigh support offered by the C6 seats, but the position is good, and the overall ergonomics inside are sound. With the top down, visibility to the rear is outstanding, and unlike recent high-beltline designs, you don't feel like you're sitting in a coffin peering out of a tank slit. With the top up, rear visibility remains decent, but it's best to double- then triple-check blind-spots before making lane changes. And while some drop-tops suck up all the trunk space when they're down, the Grand Sport is packing 11 cubic feet – just one cubic foot less than the much larger, more stately Lexus LS600h.



While the manual transmission GS coupe gets a dry sump version of the 6.2-liter LS3 V8, the convertible has to make do with the wet sump setup regardless of transmission choice -- not really an issue, as anyone who's talking sumps plans to play at the track and will take the coupe in the first place. Regardless of lubrication details, the LS3 is a marvelous piece of work. Granted, it's an architecture with a storied history, but that doesn't mean GM's powertrain boffins have let it languish. Given its small size and comparatively light weight, this latest generation makes tremendous power, and the one thing that matters in a Corvette: torque. While the GS is certainly no ZR1, 424 pound-feet of twist is nothing to sneeze at, and when the 2011 model rolls out, don't be surprised to find the LS3 replaced by a new small block equipped with direct injection to improve both power and fuel efficiency.

The convertible may not get the trick dry sump, but like all 2010 Corvettes with a manual gearbox, launch control is also part of the package. When we first tried the LC in the ZR1, the LS9 held the revs at about 4,000 RPM before letting its supercharged wrath out onto the tarmac. In the Grand Sport, enabling the stability control Competition Mode and then flooring the throttle takes the engine to a steady 4,500 RPM. Side-stepping the clutch allowed us to rip off consistently perfect launches with just enough wheel spin to hit 60 MPH in a few ticks over four seconds on a less than perfect surface. Admittedly, you won't create a billowing cloud of smoke in the process, but burn-outs don't get you moving fast – although they are fun and the GS is easily up to the task.



Back in the mid-Eighties when the C4 first arrived on the scene, the Z51 version was roundly criticized for being tuned to generate huge numbers on the test track at the expense of your spine when you ventured outside the fence. In the intervening 25 years, GM's chassis engineers have learned a lot about mechanical grip. The GS convertible does an excellent job of maintaining its composure on the worst roads Michigan has to offer without causing vertebrae misalignment. Sure, the magnetic ride in the ZR1 does a better job, but the GS has come a long way, filling in the handling and ride gap between the base Corvette and the Z06, while coming across as more useful on the road than its 7.0-liter sibling.

Chevrolet now offers a quartet of Corvette variants spanning the price range from under $49,000 to over $100-grand, giving buyers a multitude of ways to answer the age-old question: "Speed equals money. How fast do you want to go?" As the price increases, so does performance. So if a base 'Vette isn't enough to keep your better demons at bay, and you want the looks of the Z06 without the track-tuned dynamics, the Grand Sport is for you. And if you can't deny the allure of open-air motoring, for $74,170, the GS Convertible is just the ticket. Just avoid the auto wash and invest in a good sponge.