A Tale of Two Video Data Loggers for the Track
Comparing GM’s Performance Data Recorder with Porsche’s Track Precision App
Racing teams have long used data logging and in-car video to gather invaluable information for drivers and their crews. So it's no surprise the concept has trickled down to club-racing and track-day enthusiasts. With the popularity of social media and online video sites like YouTube, interest in documenting track-day outings continues to grow. Just look at how many GoPro ads circulate on television and the Internet.
Now automakers want in on the action—and the profits. GM offers a Performance Data Recorder on certain Chevrolet and Cadillac performance models. Porsche's Track Precision App is available on certain 911 and Cayman models. I tried both to learn which is a better fit for the casual track-day enthusiast looking to document and share his or her circuit circulating experiences. Here is what I discovered:
GM Performance Data Recorder
The key advantage of GM's Performance Data Recorder (PDR) is full integration. A high-definition camera lives near the rearview mirror and an in-vehicle microphone captures audio. The driver can watch recorded video (and listen to audio) through the car's touchscreen infotainment system or on a computer. Recordings transfer to an SD card, which can be plugged into a computer for easy viewing or saved onto a hard drive or to cloud-based storage.
PDR comes with both a Track Mode and a Touring Mode, the latter for spirited drives on public roads. Track Mode allows users to set a start/finish line so the system logs lap times as well as speed, rpm, and g-forces. The Performance Mode records acceleration times, including 0-100-0 mph runs. You can download the program, Cosworth Toolbox, to your computer for more in-depth analysis of saved track data (Cosworth and GM partnered on PDR). One nice extra feature is Valet Mode, which records how a parking attendant handles your car as you enjoy a meal at a fancy restaurant. Handy for preventing—well, at least documenting—Ferris Bueller-like adventures.
I played around with PDR in a Cadillac ATS-V at Circuit of the Americas. Event organizers set the start/finish line into the system before I arrived, but it's a simple process of positioning the car at the correct spot on the track and tapping a button on the touchscreen. The integrated GPS antenna triggers the lap timer each time you pass that logged spot. Using the system was as simple as plugging an SD card into the slot in the Cadillac's glovebox and touching the start button on the touchscreen. When my laps were done, I simply hit the stop button and removed the card. I plugged the SD card into my computer and watched a video with a data overlay showing lap times, RPM, track map, speed, g-forces, and more. It's a very impressive system, clearly developed by a group of engineers who know what owners need and want. Impressive. Well done, GM.
Porsche Track Precision App
Price: $1,850 for 911 GT3, 911 GT3 RS, and Cayman GT4; $1,920 for 911 R. Standard on Cayman GT4 Clubsport
Porsche's Track Precision App lacks integration. Its only real function is to communicate car data to a smartphone via Wi-Fi. Users must purchase a windshield mount for their smartphones, download the free app, and, ideally, keep their smartphones plugged into the USB or 12-volt plug, or risk a dead battery. The Porsche Track Precision App comes with no directions or a dedicated owner's manual. The only way to learn how to connect your smartphone to the system through Wi-Fi is to read the instructions noted in the app. Then there's the issue of buying a suitable windshield mount that secures your phone and gives the camera a clear view of the track, and position the phone in a place where you can still reach it without blocking your view of the track. Not easy.
I first tried the Track Precision App on a 911 GT3 RS and a Cayman GT4 at Grattan Raceway near Grand Rapids, Michigan. Grattan isn't among the selection of tracks preloaded into the app, but the system was able to plot the layout after I lapped the circuit and marked the start/finish line. After the first hot session, I reviewed the footage and found the windshield mount was shaking far too much for a clear picture. For the second session, I forgot to put my phone into airplane mode (make sure to manually turn Wi-Fi back on) and an incoming phone call disrupted the recording. Run three finally allowed some decent footage, but the windshield mount was still compromising the quality. Once I got home, I used iTunes to extract the video from my iPhone to my computer but the data overlay—rpm, speed, lap times, etc.—didn't stay with the video. If you want to see the complete video with data, you need to view the recording on your iPhone. So, the first round with Porsche Track Precision App was rather unimpressive.
I did more research before my next track day, which was in a Porsche Cayman GT4 Clubsport race car (full story coming soon). I read other complaints online about Porsche's system but I persevered, determined to get the app to work correctly.
I bought a windshield mount that had good reviews on Amazon and used a dedicated iPod Touch instead of my iPhone, so I didn't have to worry about incoming calls. Unfortunately, the new windshield mount kept bumping the side buttons on the iPod. Once I got that sorted with a modified iPod case, the GPS on the iPod wasn't talking with the Porsche app. That's when I figured out that the iPod Touch doesn't have GPS. So, I switched back to my iPhone, which didn't have enough storage space remaining. Deleting a load of photos fixed that, and I finally got some footage and data during a warm-up session before running into further storage space issues. Once I got home, I used a trick I found on the internet and used QuickTime on my Mac to take a screen recording of my iPhone as I played the video. This allowed me to extract the video with the data overlay onto my computer. Well, at least until another phone call interrupted that process. Frustrating.
GM vs. Porsche
Porsche has a lot of catching up to do in regards to OEM video and track data systems. GM deserves kudos for developing a fully integrated system that is simple to use and has a load of features. Certain aspects of Porsche's Track Precision App are impressive, such as its ghost car feature, the ability to log multiple drivers, and an optional motorsports-like lap trigger, but the German company needs to incorporate it into the main touchscreen and fit an integral camera and SD card slot. Porsche's brilliant, track-friendly cars deserve better.