Dr. Diandra Leslie-Pelecky at Building Speed has an in-depth look at the tire issues encountered last weekend in the Food City 500 NASCAR Cup Series race at Bristol Motor Speedway.
A few excerpts:
How Were the Tires Different?
They weren’t.
The Bristol tire codes (D-5170 and D-5206) are the exact same ones used at the 2023 fall Bristol race.
How was the Track Different?
Bristol used ‘The Resin’ in the lower groove rather than the PJ1 TrackBite applied last year. Greg Stucker, Goodyear’s director of racing, explained that they made the switch because of a February 2024 tire test at Bristol.
What’s the Difference between PJ1 and ‘The Resin’?
Even before the Next Gen race car, some tracks started using track preparation compounds to increase grip in one or more lanes. Tracks owned by Speedway Motorsports, Inc. (SMI) started the trend using PJ1 Track Bite. This compound is a traction-enhancing liquid originally developed by the Sperex corporation as a high-temperature coating for NASA.
So Why Did the Tires Wear So Much?
No one knows the answer to why there was so much tire wear at this race. But I can guess at what Goodyear is doing to try to figure it out.
- I’m sure they did more friction testing than usual after the race so that they can compare the conditions with those after the fall 2023 race.
- Once they realized there was something different, I suspect that Goodyear’s tire engineers made more temperature measurements than usual. That’s data that can only be captured at the track.
See much more at Building Speed.