It was headline news, and you heard it here first: The mid-engine C8 Corvette can hit 60 mph in as little as 2.8 seconds. It’s an incredible engineering achievement considering the car is rear-wheel drive and makes less than 500 horsepower. Usually, at least one of those two things needs to be improved upon to generate that kind of acceleration. As we’ve discovered after testing four different C8s, including our new 2021 Chevrolet Corvette Z51 long-term car, the launch control doesn’t get it right every time.
The car that managed the 2.8-second run was the second we tested. The first needed 3.0 seconds flat, the third needed 3.3 seconds, and our long-term car needed 3.1. In theory, the launch control system fitted as standard should have them all accelerating the same, so what’s going on here?
The first place to check is the curb weight. The heavier a car is, the longer it takes to get moving if the power output doesn’t change. What options and features a given car is equipped with can make a big difference in how much it weighs compared to what’s quoted in the manufacturer’s spec charts, which is why we weigh every car we test. Unfortunately, it’s no help here. The quickest car was not the lightest, and the slowest car was not the heaviest, so it’s not simply a difference in how much each car weighed as configured. The only thing we do know is the slowest car was the only one not equipped with the Z51 Performance package, so its run is excusable. The other three? Read on.
Going to the test drivers’ notes provides the answer. Here’s an excerpt from the recent test of our new long-term car by associate road test editor Erick Ayapana: “Never felt like I got a solid launch since LC could not regulate wheelspin or throttle well enough.”
Not All Launch Control Is Created Equal
When we test a car, we don’t just run it down the track once and write down the result. We perform multiple runs using various techniques in order to get the best result. In the case of vehicles with launch control, we’ll use the system and then launch the car manually to see if our expert test drivers can beat it. Whether or not they can depends on how effective the launch control system is, which depends on how sophisticated the system is.
Getting a good launch requires holding the brake pedal down and bringing the engine up to a speed where it’s producing a lot of power, but not so much it will overwhelm the rear tires and cause them to spin. Then, it requires releasing the brakes and applying full throttle in such a way that doesn’t overwhelm either the tires or the engine. A good launch generates either zero or next to zero wheelspin. Ideally, the exact right amount of power is applied to the tires at the exact right time and the car takes off with no drama because you’ve found the exact amount of power that can be put to the tires without overwhelming them. A small amount of wheelspin, which is the tire spinning against the pavement for less than a full rotation, can also return a good launch. This is the chirping noise you sometimes hear when a car accelerates hard.
A rudimentary launch control system simply does the basic throttle application for the driver, revving the engine up to a preset speed and applying full throttle once the driver releases the brakes. It makes no attempt to modulate the throttle or apply the brakes to prevent the engine from overpowering the tires. A highly sophisticated one will manage both the throttle and even apply individual brakes as needed to eliminate as much wheelspin as possible.
The C8 Corvette’s Launch Control
The C8 Corvette’s launch control falls somewhere in the middle. It’s sophisticated enough that our test drivers can’t beat it (not the case with previous Corvettes), but it’s not the best we’ve experienced. As Ayapana wrote in his notes, our long-term Corvette struggled to control wheelspin, meaning the car wasn’t taking full advantage of either its power or its traction. As a result, it couldn’t hit that incredible 2.8-second number, just a slightly less incredible 3.1 seconds.
To be sure, we did repeated runs as we always do. The most sophisticated systems will learn from each run, recording the amount of wheelspin and adjusting its reaction on the next run. This is necessary to account for all the variables that determine traction including tire temperature, pavement temperature, the type of surface, how clean or dirty the surface is, and more. Unfortunately, the Corvette showed no ability to “learn the surface,” as we call it, so additional runs didn’t produce a better result. We checked with Chevrolet, and the software hasn’t changed since the first car we tested, so we’re confident in this conclusion.
The C8 Corvette Is Still Damn Quick
Let’s not take much away from the C8 here, though. 3.1 seconds to 60 mph is still an incredible achievement, and our testing shows that changing variables such as surface, surface temperature, and more could result in a quicker time. It just means you’re stuck dealing with some variables beyond your control because the car isn’t as good at adapting to them as the best systems on the market. Thankfully, it’s something that can be improved with more software development, and we hope Chevrolet will do so in the future.
The Rest of the Results
All that sorted out, here are the rest of the numbers. Continuing on past 60 mph, our C8 traps an 11.4-second quarter mile at 120.4 mph, which is seriously moving. Serious stopping from 60 mph is achieved in 99 feet, and anything under 100 qualifies it as a supercar in our book. Going around a corner, it pulls a supercar-worthy 1.01 average lateral g, and with a 23.4-second figure-eight lap at 0.86 average g, it’s supercar adjacent though far from the top of the list. Swap the standard Michelin Pilot Sport 4S tires for a set of Pilot Cup 2s like most of the list-topping cars wear, and you might see a better result. We may just try that down the road.
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