If he gained so many positions, how did he end up fifth? He lost 16 positions during pit-stop cycles. That produces a pass differential of +16, meaning that he gained 16 more positions than he lost. Over the course of 420 green-flag laps, he made 31 passes and was passed 15 times. Larson started fifth at Bristol and finished fifth. I examined each green-flag segment, noting Larson’s positions at the start and end of each segment, and how many times he changed position in-between.
Caution laps are shaded yellow, although you can probably infer cautions from the position changes. The next graph shows Larson’s running position as a function of lap number. Counting accurately is confusing enough as it is. Bristol is a good race for this type of analysis because there were no green-flag pit cycles. Using that data, I developed a different kind of passing metric. What I can access is each driver’s running position each lap. NASCAR doesn’t make detailed loop data publicly available. But that’s not what loop data is designed to measure. I view passing as capturing a position and holding it for more than a straightaway. But did it really take him 154 passes to go from 23 rd to second?Īlthough Elliott’s transponder switched positions with other cars’ transponders 154 times, not all of those events are what I think of as “passing.”
What I hadn’t appreciated until I dove into these numbers is that they’re not exactly what you think they are at other types of tracks, either.Īccording to loop data, Chase Elliott made more green-flag passes than any other driver at Bristol. That doesn’t measure passing in a way that illuminates the racing. Those extraordinarily large numbers just tell us that two or three lanes of cars traded positions a lot. I’ve always been skeptical of passing metrics at superspeedways. Because races are different lengths (and tracks different sizes), it’s hard to compare data.īut superspeedway races stand out for having thousands more green-flag passes than other types of races. The graph below shows green-flag passes by race for the 2022 season. The loops capture a car’s precise position on track - and its position relative to other cars.
Wire loops embedded in the track (and on pit road) record each of these signals. Loop dataĮach car carries a transponder that emits a signal unique to that car. But they also don’t give up their truths easily.
So are the drivers wrong? Perhaps their comments reflect the accumulated frustration of a long night plagued by so many equipment problems? That’s 980 passes more than the 1,710 green-flag passes recorded for last year’s fall Bristol race. NASCAR’s loop data reported 2,690 green-flag passes for the 2022 fall Bristol race. Kevin Harvick and Denny Hamlin, among others, felt the car made it too hard to pass.īrad Keselowski agreed that it was hard to pass, but opined that it’s supposed to be hard. Drivers expressed some strong opinions about the Next Gen car’s passing ability after Bristol.