Feature update: Restart Speed Percentile (RSP)
Restart Speed Percentile is now available on Lap Raptor. Here is how it works, where to find it and who leads each NASCAR series.
Restart Speed Percentile, or RSP, is live now. NASCAR’s live feed reports each driver’s Average Restart Speed during a race. RSP takes the final positive value, ranks it against the other drivers in that race and turns it into a score from 0 to 1.
We use a percentile here because miles per hour cannot be compared fairly across tracks — speeds at Daytona are near 200 mph, whereas at Martinsville they are around 90 mph.
You can find RSP on the dashboard and the Advanced driver reports for Cup, O’Reilly and Trucks. Individual race Advanced reports show the underlying Average Restart Speed. The latest Cup race has an Advanced report and restart-speed charts.
Here are the leaders through July 20, using the normal report minimum of 10 starts for Cup and O’Reilly and seven for Trucks.
| Driver | Starts | RSP |
|---|---|---|
| Tyler Reddick | 21 | 0.7656 |
| Chase Briscoe | 21 | 0.7602 |
| Denny Hamlin | 21 | 0.7459 |
| Ryan Blaney | 21 | 0.7106 |
| Chase Elliott | 21 | 0.7072 |
RSP is only available from 2025, which is when we started tracking the live feed data.
