The Grand Sport vs. Grand Sport X comparisons we'd seen before had one thing in common. They set a Z07-package Grand Sport against a touring-spec Grand Sport X. That means carbon wheels, Z07 aero, and Cup 2R tires on one side, and a hardtop convertible on Michelin Pilot Sport 4S tires with no aero on the other. There's no track package for the Grand Sport X right now, so the two cars were never set up the same way.
That tells you how the equipment compares, not how the cars compare. We wanted to find out whether the X makes a meaningful difference when the configurations are matched. So we took both cars to Putnam Park.
The Setup: Two Cars, One Configuration
Both cars ran the following:
- Factory Michelin Pilot Sport 4S tires
- Factory brake pads
- GM-recommended track alignment settings
- Verus Engineering WCW rear wings
- High-temperature brake fluid
One car was a Grand Sport Coupe. The other was a Grand Sport X Hardtop Convertible. With tires, brakes, alignment, and aero matched, any difference on track would come from the cars themselves.
The Driver: Aaron from Winning Formula
We handed both cars to Aaron from Winning Formula. His background includes a Putnam Park record and race wins in GRIDLIFE, World Racing League, and the Zenith Racing Series. He builds and develops Porsche and C8 Corvette race cars for a living and owns a C8 Stingray himself, so he knows both the platform and the track.
Putnam Park suits this kind of test. It's a 10-corner circuit built as a testing facility, with plenty of runoff and a layout that leans toward high-speed corners. Aaron described it as a middle-of-the-road track, with only one low-speed corner and a modest straightaway.
The Results on Pilot Sport 4S Tires
Aaron's first impression was that the cars felt very similar. Getting out of one and into the other, he said it felt like the same car, apart from the sensible differences that come from having a hybrid drive on the front axle.
The matched 4S laps landed close together:
- Grand Sport: 1:13.87 and 1:13.88 on back-to-back laps, with clean track and no traffic.
- Grand Sport X: 1:12.8, about a second quicker, even though Aaron caught a slower car and had to recalibrate for his flyer.
Aaron said the X lap felt easier. He also said that with more time in both cars, he wouldn't expect the gap to grow or shrink.
What the Hybrid System Does on Track
The X carries a front motor, and Rob put its weight at around 300 pounds, so the obvious worry is that you'd feel it. Aaron didn't. He never felt like he was driving a larger, heavier, or handicapped car, and the basic chassis behavior felt substantially similar to the Grand Sport.
A few of his observations stood out:
It doesn't pull you off the corner. Many owners assume front-axle drive will tug the car out of a turn like a traditional all-wheel-drive car. Aaron said the front motor doesn't make enough output for that, and the rear end still drove the car off the corner. When the rear stepped out, the front drive didn't try to square the car up.
Charge Plus works like a ghost trail-braker. With the system prioritizing regeneration, Aaron felt a faint, engine-brake-style drag on the front axle even off the brake pedal. He compared it to the light brake pressure drivers carry into a corner to keep weight on the nose. It helped pull the nose toward the apex but never enough to over-slow the car. When he picked up the throttle, the rear took over.
It makes the car feel stable. Aaron described the car as stable from braking to apex and said the hybrid drive never felt like a detriment.
Battery management is manageable. There's one more thing to think about lap after lap. Aaron ran Charge Plus on for some laps and switched it off when he wanted a flyer. With Charge Plus on, he said the X feels like the Grand Sport. He thinks you could run quite a few laps back to back using push-to-pass in regen mode. The controls are on the steering wheel, which is easier to reach than the E-Ray's, where they sit down by your right knee.
The hybrid drive in the X is the same unit as in the ZR1X. On a track with a longer straight than Putnam's, Aaron noted that battery deployment could matter more.
Adding Cup 2R Tires
The Grand Sport can be ordered with Michelin Pilot Sport Cup 2R tires, but the Grand Sport X can't. To see what the tire alone is worth, we put a fresh set of Cup 2Rs on the X.
Aaron went out with the faster group and ran a 1:10.6, more than two seconds quicker than his 4S lap. He called the 4S a good wet-weather and sporty daily tire, but not an optimal dry-weather track tire.
Based on his experience with Z06s, Aaron thinks a Grand Sport X on Cup 2Rs would run about the same lap time as a Z06 Z07 on the same tires at Putnam Park. He recalled a Z07 running a low 1:10 on Cup 2Rs in slightly better conditions, though he couldn't remember the exact number. In his words, the X felt "very Z07-ish" on those tires.
Which Would You Pick?
We asked Aaron: money is no object, you can't modify the car, which one do you buy? His answer was the Stingray. His reasoning was practical. It's the easiest car to use, it's narrower on a trailer, there are more tire options, and there's less guilt about wearing out a car on track.
He was clear about the other side of that choice, too. Whenever he starts a Z06, he thinks it's special, and he figures drivers coming from high-revving platforms will want one. The Grand Sport, in his view, feels like a traditional Corvette, with the grunt you'd expect from a pushrod V8. He suspects the Grand Sport and Grand Sport X get overlooked because buyers stretching to that price point often go straight to the Z06. At the time of filming, a Grand Sport Z07 was over $22,000 less than a Z06 Z07, MSRP to MSRP.
That leaves a lineup with a car for every kind of C8 owner: narrow-body Stingray, wide-body Grand Sport, all-wheel-drive Grand Sport X, supercar-territory Z06, and turbocharged ZR1. Aaron's take on the X is that the traditional track buyer may not go looking for it, but an owner who ends up at the track will probably be pleasantly surprised. Put Z06 tires on it, and you can nip at the heels of a Z06.
The Takeaway
With matched configurations at Putnam Park, the Grand Sport X was about a second quicker than the Grand Sport on Pilot Sport 4S tires, and the hybrid system never hurt the car. Aaron felt the front drive helped stability from braking to apex. On Cup 2R tires, the X ran 1:10.6.
This is one driver, one track, and one day, so treat it as a data point rather than a final verdict. It does suggest that the Grand Sport X is more capable on track than its touring-car image implies.
Build Your Grand Sport or Grand Sport X With Paragon
Paragon Performance builds and tests parts on our own shop cars at our Waukee, Iowa, facility. Start with our Grand Sport and Grand Sport X parts, or go straight to the category you're building around: exhaust, wheels, or suspension.
- Shop Grand Sport and Grand Sport X Parts
- Find an Installer
- Talk to Our Team
- Watch the Build on YouTube
Which would you take to your next track day, the Grand Sport or the Grand Sport X? Tell us your pick in the comments on the video.
Parts and partners: Winning Formula · Verus Engineering
