Porsche Track Precision

Porsche Track Precision data, read like a coach

The Track Precision app records excellent data: speed, throttle, brake pressure, steering, g-forces, yaw, gear, RPM and the stability-control flag, twenty times a second. It just doesn't tell you where you are losing time. Export the session, drop the file into Pitwall, and get that answer corner by corner.

Analyze a Track Precision sessionDownload a real export (1.4 MB)

How to export a session

  1. In the app, open the session you want. Each outing is a session; export the one you want to look at, or several from the same day.
  2. Use the session's export (share) function and choose the data export. It produces one CSV file per session. Send it to yourself, or save it to Files; on a phone you can share it straight to the Pitwall page.
  3. Drop the file into Pitwall. Up to six sessions from the same car and track at once. Pitwall recognizes the circuit from the GPS, places the official turns, and builds the debrief. Nothing is kept unless you save it to your garage.

Pitwall works with the Track Precision app on the cars that support it (718 Cayman GT4 and GT4 RS, 718 Spyder, 911 GT3 and GT3 RS, GT2 RS and other Porsches with the Sport Chrono package). The example session on this site is from a 718 GT4 RS.

What is in the export, and what Pitwall does with it

ColumnUsed for
timestamp, latitude, longitudeCutting laps, lining every lap up on the fastest lap's path foot by foot, recognizing the circuit and placing its official turns.
velocityThe speed trace, minimum and exit speeds, the running time delta between laps, and the theoretical best.
pedalForce (throttle)Pick-up point, hesitation on exit, lifts where the reference stayed flat, coasting between brake and throttle.
brakePressureBraking point, time to peak pressure, release rate, trail-braking overlap into the turn.
lateralAcceleration, longitudinalAccelerationThe grip circle, peak braking g, combined grip through turn-in, and the "more grip here than you have used" call.
steeringAngle, gierrate (yaw rate)Car balance: understeer mid-corner and the rear stepping out on exit, calibrated on this car's own data first.
electronicStabilityProgram (PSM)Every exit where PSM cut in is named, with the corner it happened in.
engineSpeed, currentGearShown on the traces and in the onboard view; gear changes are a precise point to sync video on.
laptimeThe app's own lap timer confirms the start/finish line.

Because every channel the coaching rules need is measured, a Track Precision export gets the complete set of calls: braking, throttle, trail braking, grip, consistency and car balance. The rules and their thresholds are on the methodology page.

What you see that the app doesn't show

A theoretical best from your own lapsYour fastest clean time through every corner, stitched into one lap. It is the reference for everything else, because it is a lap this car and this driver already did, in pieces.
Time lost per corner, rankedWhere the tenths are, in order. The three biggest come first with one finding each, the evidence, and a drill.
PSM interventions, by cornerThe export's stability-control flag becomes a coaching call: "stability control is cutting in on exit" at the exact turn, so you can decide whether to ask the car for less or change the exit.
Car balance from steering and yawHolding more steering than the car's turn rate asks for is understeer; rotating faster than the steering asks for on the power is the rear stepping out. Both are read from the data, not guessed.
Lap comparison and videoAny lap against any other, or against the theoretical best, with the delta, the map and the traces zoomed to a corner. Add your in-car footage and watch it with the data drawn over it.

Quirks of the export, handled

  • The last lap ends a car-length early. The app stops the export the moment it sees the car cross its line, often 30 to 60 m short of where the GPS trace crosses it. Pitwall closes that lap from the car's speed and acceleration, counts it as a full lap, and labels the estimated final metres.
  • Uneven timestamps. Readings arrive at roughly 20 a second with small gaps; Pitwall resamples everything onto one timebase, and a real gap in the recording is flagged rather than interpolated into fake driving.
  • Metric units in the file, your units on the page. Speeds are converted to mph or km/h, distances to feet or metres, with one switch in the header.
  • Several sessions, one car. Load the morning and afternoon sessions together and the theoretical best uses the best of both; the garage keeps each file under its track and car.

See a real one

The front page's example is a Track Precision export from a 718 GT4 RS at Road America: four timed laps, best 2:22.91, about two seconds on the table against the theoretical best, with three corners to fix. Open it on the front page, read the turn-by-turn version on the Road America page, or download the export itself and drop it in to see the whole flow before your next track day.

Open the example debriefDownload the export

Try it on your last session

Free while in beta. No account needed.

Analyze a sessionSee a real debrief