Using Sport Chrono

[obiwan]

I decided to try out my Taycan on the track last weekend (first time for me to track anything). I discovered some things with the Sports Chrono feature I thought I'd pass on.

• If you are on a unknown track like I was, there is an option to just manually record. But for me it didn't automatically detect the laps, and I was concentrating too hard to click the "lap" button on the steering wheel. The data is still good though. I didn't research how to set up a "reference lap", which was in the GUI as well.
• It's in the car's manual, but "track endurance mode" can only be enabled >= 65%. One time I was at 64% and it didn't work, so that's a "confirm". From what I can tell, all it does it keep the battery cool?
• That being said, I didn't get performance limited even without track endurance mode enabled. I do have a J1.2, but I believe I've seen references that even the updated battery can get limited if it overheats. I assume I was ok only because I wasn't able to push the car to it's limits (though it all seemed excitingly/terrifyingly fast to me... 20-25 minutes on a 2mi loop, two straights where I could hit ~120/~140).
• You can export the Sport Chrono recording by connecting a USB drive to either the top (USB-1) or bottom (USB-2) in the center console. BUT the copy silently fails unless the USB drive is formatted as MS-DOS (FAT) + Master Boot Record. This was super confusing.
• RaceRender 3 can interpret a SportChrono export file and create a visualization, though I haven't fully figured out everything it can do (so far I have a video-like viz of the track, placement of the car, speed, and brake pressure. G-force seems wonky, so I think I have something wrong). There are two export options (regular and backwards compatible). RaceRender 3 was only able to open the backwards compatible version of the file.

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[tcam999]

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[Flying ace]

Wow, awesome summary. Thinking of the taking the Taycan on Sonoma

 

[obiwan]

Quick update as I managed to get RaceRender 3 (RR3) to work with the help of Claude. Well, mostly work.

The first challenge I faced was that my dashcam is FitcamX which produces 60 second clips. I'm on MacOS so I used homebrew to install ffmpeg and these two commands helped me create one big video file:
===
# front camera is in the wrong format (I think due to 4k), re-encode and combine
ffmpeg -i "concat:$(ls -1v *.TS | paste -sd '|' -)" \\n -c:v h264_videotoolbox -b:v 40M -pix_fmt yuv420p \\n -c:a aac -b:a 192k -movflags +faststart combined.mp4

# rear camera is already the right format, just combine them into one file
ffmpeg -i "concat:$(ls -1v *.TS | paste -sd '|' -)" \\n -c copy -bsf:a aac_adtstoasc combined.mp4
===
The commands assume you have a dir of TS files you want to mash together.

Step 2 was getting the video/data into RR3. On a Mac the install is weird. It complains about missing templates. Turns out you have to make a directory called "RaceRender 3" under ~/Documents and then copy the dirs "Images Styles Templates Video Positions" from the RR3 install location to there. I used the "Data Overlay + Rear Video" project template (as I have a rear cam as well as front). Then used "Standard Template 1" which shows speed/G forces/throttle/brake/lap time on the bottom and a top down view of the track with car position on the top.

Step 3 was getting all of the metrics working. This took awhile. I kept trying to fix things in the GUI. It appears the Taycan produces an export that confused RR3 (possibly because it's an EV and doesn't have some things like gears, a tach, etc..). I fed the file into Claude and it made me a Python script that can conver the Taycan export into a CSV that RR3 liked. This loads cleanly without having to tweak anything.

Step 4 was getting the metrics and video in sync. I used the "data sync wizard" and used "lap 3 start". This basically figures out there was a ~8.5 second offset between the video and data.

At this point it was all working great... at first. But it drifted the longer the video went on. Claude said the problem was it assumed a 1 hz sample rate for the conversion it did but the real sample rate must be slightly faster/slower. There were two options: to tweak the video playback speed or modify the data timing. I had it do the second, and fed it the timestamp of my first lap crossing and last lap crossing. This indicated a ~3% slower sample rate from 1Hz. It tweaked the data input file, and it's much better now. Though it still drifts a little bit at the end (maybe 1 second off).

This took way too long the first time, but when I do this again it should be pretty easy.

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