Cars —

The Corvette Z06 is a 650-horsepower video camera

Trying out the Corvette's built-in data acquisition system.

The Corvette Z06 is a 650-horsepower video camera
Jonathan M. Gitlin

On a recent trip to Ann Arbor and Detroit, General Motors was nice enough to lend us a new Corvette Z06 as a runabout. Although Cars Technica is always up for getting some wheel time with interesting sports cars, the fact that the Z06 was equipped with the Performance Data Recorder (PDR) really piqued our interest. In fact, it has been an option on Corvettes for a little while now; last year it made news because of its 'Valet mode,' something that may not be legal in some states. The PDR combines a 720p video camera with an in-built data acquisition system, bringing driving analytics easily within grasp. A full workout of the PRD's capabilities will have to wait for me to successfully persuade The Powers That Be to let me book some track time on the office dime. But a (relatively) sedate drive through the Michigan countryside with Ars' Lead Developer Lee Aylward seemed like a good time to try out the PDR on the road.

Automotive Editor Jonathan Gitlin and Lead Developer Lee Aylward go for a drive in the countryside. Edited by Jennifer Hahn.

One of the nice things about the relentless pace of Moore's law is the way that consumer-grade hardware enables us to do things that a few years ago would have required six- or even seven-figure price tags. For example, in the car world, cheap and rugged video cameras, processors, and GPS units have brought data recording systems to the masses. Almost no one goes on a track day or racing without a GoPro camera, for example. And data recorders like those from TraqMate and AutosportLabs make it a doddle to analyze one's driving quantitatively and then overlay that data graphically on top of the corresponding video. Some automakers are evidently wising up to this trend and as a result are starting to offer OEM solutions built into their cars. Porsche now offers a Track Precision app which leverages a smartphone's camera to record video and overlay telemetry data, but Chevrolet was first to market with PDR, a standalone solution.

PDR uses a camera set into the base of the rear-view mirror, just below the top of the windshield, coupled with a microphone inside the cabin. So far, so interesting, but nothing you couldn't get from a GoPro. But the PDR—developed in a partnership with Cosworth, which also supplies the telemetry system used by Corvette Racing—couples video and audio recording with a telemetry module. This features a dedicated GPS system operating at 5Hz, separate from the one in the car's infotainment system (which only runs at 1Hz). The PDR is also connected to the CANbus, allowing it to pull information from the car's sensors, like which gear you're in, engine revs, throttle and brake applications, steering input, and so on. All of this is then recorded to an SD card, found in the glove box.

You activate PDR from the infotainment system, choosing from five different modes. Track overlays the greatest amount of data, including a map of the circuit you're driving on (pulled from Bing) and lap times, as well as two axes of G forces. Sport overlays less data but still shows lateral Gs, speed, rpms, and what gear you're in. Performance lets you measure things like 0-60mph times, Tour is just audio and video with no data, and finally there's the somewhat-controversial Valet mode. Once you've finished recording, you can either play back the video from inside the car, using the Corvette's infotainment screen, or pull the SD card and export the video just as you would any other camera. Corvette has also developed a Windows app called Cosworth Toolbox that lets you dive into your data, so you can analyze your driving and look for where you could improve it.

Since we weren't at a track, nor were we figuring the car's performance, we went for Sport mode. As you'll see from the video, the PDR does an OK job of recording audio even with the roof down. The video quality on the other hand is OK but not amazing; a dedicated GoPro will offer much greater resolution and better handles changing light conditions, and the camera's mounting casts a shadow over the top left corner of the frame. But conversely a GoPro will require suction-mounting to the screen, and you need to remember to charge it (and not to set it to photo burst, as I foolishly did when I got a chance to ride in the Formula E safety car earlier this year). What's more, unless you also shell out for a TraqMate (at least $549) or a RaceCapture/Pro ($429), you can forget about overlaying any of the car's data on top of your movies.

PDR comes as standard on Corvettes with the 3LZ trim package but can be added to 1LZ- or 2LZ-equipped cars for $1,795, so it's not the cheapest solution out there. Hopefully in the near future we'll get a chance to see how it compares on the track to Porsche's Track Precision app and stand-alone solutions [if you're reading this Nate, I think it's a good idea]. But for sheer ease of use and convenience, we liked it, and the Valet mode seems like good peace of mind, assuming you're using it legally.

Specs at a glance: 2015 Chevrolet Corvette Stingray Convertible
Body type 2-door convertible
Layout Front engine, rear wheel drive
Powerplant 6.2L supercharged V8
Transmission Seven-speed manual with Active Rev Match
Horsepower 650 bhp @ 6400 rpm
Torque 650 lb-ft @ 3600 rpm
Steering  Variable ratio rack & pinion (electric power assist)
Suspension Short/long arm (SLA) double wishbone, cast aluminum control arms, transverse-mounted composite springs; adaptive magnetorheological dampers
Tires Michelin Pilot Super Sport run flat
Front: P285/3Z0R19
Rear: P335/25ZR20
Top speed 180 mph+
Fuel economy (City/highway) 15 mpg/22 mpg
Weight 3,582 lb (1,625 kg)
Wheelbase 106.7 in (2,710 mm)
Dimensions 177.9 in (4,518 mm) x 77.4 in (1966 mm) x 48.6 in (1235 mm) (LWH)
Base price (2015 model) $79,995
Price as tested (2015 model) $93,645
Options added 2LT trim package, Carbon Fiber Package, Performance Data and Video Recorder, Carbon Fiber interior package, Z06 black aluminum wheels, Carbon flash painted spoiler and outside mirrors.

That's quite a lot of words about a rather brief use of the PDR, but we'd be remiss if we didn't also discuss a bit about the car it came in. We were very impressed with the Z06's cheaper, less powerful sibling, the Stingray, when we tested one last year. And we stand by our opinion that there's no better-looking, front-engined sports car on the market right now. The Z06 starts at $25,000 more than a Stingray, for which you get a slightly wider car with a correspondingly wider front and rear track (i.e. the wheels are slightly farther apart). The wheels and tires are an inch bigger and wider (1.5"/3.8cm front, 2"/5cm rear) than the Stingray, the brakes are larger, and there are a number of additional air vents and scoops to cool the engine, brakes, and gearbox.

The engine is maybe the most significant upgrade. Out goes the naturally aspirated 6.2L LT1 V8, in comes the supercharged 6.2L V8 LT4. This is good for 650hp (484kW) and 650lb-ft (881Nm), making it the most powerful production Corvette ever. It sounds fantastic, too. The car features the same magnetorheological suspension as the Stingray and the same five different driving modes (Weather, Eco, Tour, Sport, and Track). In the first three, the exhaust is muted, and from the cabin the main thing you hear is the whine of the supercharger. Switch into Sport or Track, however, and valves open up giving it a deep-throated roar that still makes us giggle every time we hear it.

That engine also makes the Z06 extremely fast. With the 8-speed automatic transmission, Chevrolet say it will hit 60mph (97km/h) in 2.95 seconds. Our car, fitted with the 7-speed manual gearbox, takes a more sedate 3.2 seconds, which makes it as rapid as the Tesla P85D's Insane mode—or the legendary McLaren F1. Top speed depends on whether it's a coupe or convertible and which of the aerodynamic packages are fitted, but Harlan Charles, Corvette's product manager, told us even our car—fitted with the draggy $2,995 carbon fiber package—should be good for the other side of 180mph (300km/h). Away from a race track, we actually think the Z06 may be a little too fast. Even when the tires are warm—something you can check easily from the car's multifunction dash—it will break traction in the lower gears, and on public roads we never felt comfortable pushing the car anywhere near the edge of its vast performance envelope. That said, it's quite possible to drive the car sedately and with respect to traffic laws, and in Eco mode it'll even return 22mpg thanks to the same cylinder deactivation mode that's now common across GM's V8-engined vehicles.

As a track car, we think the Z06 represents fantastic value for money; the coupe starts at $79,995 and the convertible is an extra $4,000. It's also the first car, other than some Ferraris, that comes with Apple's CarPlay, although only from 2016 models. We're struggling to think of another sports car that offers as much power for close to the price, and, with the latest generation, the Corvette finally has an interior that won't make owners embarrassed compared to its German or Italian rivals. As a road car? To be honest, we think the Z06 is overkill. The extent of its performance is such that you need a track to exploit it [are you listening, boss?], making the cheaper but-just-as-good-looking Stingray (with the Z51 option) a more sensible proposition for day-to-day use.

Channel Ars Technica