Spring Martinsville goes from 500 laps to 400 laps to accommodate a night race. How will that change the race time?
Race Times at Martinsville
We’ll look at races from 1990 to the present. Martinsville races during this period have always been between three and four hours.
The one exception is the spring race of 1995, which was shortened by rain.
Of races that ran at least 500 laps:
- The shortest full race was fall 1996, which ran 3:11:54
- The longest race was fall 2007, which ran 3:59:45
- The mean race time is 3:40:14 with a standard deviation of 11 minutes. This means most races fall between 3:29 and 3:51.
A Closer Look at Race Times
Let’s look at the same data from above, but set the y-axis to show only between 3 hours and 4 hours so we can see these differences more clearly.
Looking at the data this way shows that there’s a correlation between race length and number of cautions — as you might expect. The more cautions, the longer the race takes. There is some variation, of course. We had 15 accidents in each of the last two races, but the spring race was 12 minutes longer.
Race Times vs. Number of Cautions
So let’s look at how race time depends on number of cautions. The graph below separates spring races (red) and fall races (green). There isn’t much difference between fall and spring, with one notable exception: There are more races with more than 15 accidents in the fall than in the spring.
The mean number of cautions is 12.35 with a standard deviation of 3.6 — meaning that most races have between 9-16 cautions.
Ignoring the rain-shortened race (which still managed 7 cautions), you see a pretty linear trend. Given that we’re guaranteed two cautions from stages, the shortest a 2022 race could be is about 190 minutes, or 3 hours, 10 minutes.
We can’t tell from this data whether the large number of cautions at fall races is due to the races being at night or simply from being later in the season when drivers are more desperate for wins. But this graph predicts an average race length of around 210 minutes (3 hours, 30 minutes).
A race starting at 7:30 pm would, on average, end around 11:00 p.m. But if we had a larger-than usual number of cautions, it could stretch to midnight.
Shortening the race to 400 laps brings the average race time to about 2 hours, 48 minutes, with a potential maximum race time of about 3 hours, 20 minutes. That ensures the race ends well before midnight.
NASCAR official race times do not include red flags. If there is an incident — weather, or a big wreck — that brings out the red flag, the actual time you’re at the track could be much longer than the official race time.