How to compare racing lines with GPS
Put two laps on top of each other and look for where the lines stop matching. Then check the speed and delta. The prettier or shorter line is not automatically better—the line that leaves the section faster is what matters.
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The main idea
A line is better when it gets you through the whole section faster and you can repeat it safely. The neatest or shortest-looking line is not automatically the fastest one.
What to look at
- Approach position and path length
- Where the path begins curving
- Apex region rather than one exact pixel
- Track-out and resulting exit speed
Try this
- Use laps recorded close together
- Align them by track progress
- Inspect one corner at a useful zoom
- Pair every line difference with speed and delta
- Confirm meaningful changes with onboard video
Keep in mind
Consumer GPS has positional error, and satellite tiles may be offset. Do not infer exact inches of track usage or an exact apex solely from the map.
FAQ
Why is my GPS line beside the track image?
GPS and map tiles can each have offsets. Compare the laps relative to one another and use video for exact track placement.
Is the shortest line fastest?
Not necessarily. Radius, grip, vehicle direction, and exit speed can outweigh a shorter distance.