How to read a lap-time delta trace
Delta is the easiest way to find where a lap changed. When the line moves, one lap is gaining or losing time. When it goes flat, nothing new is happening—the lap is just carrying the gap it already created.
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The main idea
Delta is a locator. It tells you where to investigate, while the map and channels explain what differed. A corner that gains 0.2 seconds but loses 0.3 on the following straight is not a net improvement.
What to look at
- Where the delta first changes direction
- Whether the change is gradual or sudden
- Whether a gain remains through the next section
- The matching speed, line, and acceleration traces
Try this
- Align clean laps by track distance or progress
- Find the first large slope in the delta
- Mark its start and end on the map
- Inspect the corner phase just before the change
- Continue forward to see whether the result persists
Keep in mind
Ignore tiny wiggles. GPS and timing alignment can make the line move a little. Pay attention to a change that is easy to see, happens in one clear section, and shows up again on another lap.
FAQ
Why can delta change after the apex?
The time effect of an earlier action often accumulates later. Exit speed can keep changing the delta down the following straight.
What does a flat delta mean?
The current time gap is being maintained. It does not necessarily mean both drivers are using the same line or inputs.