Goodyear will provide a new right-side tire for this weekend’s NASCAR doubleheader at Auto Club Speedway.
The new tire construction will be used in both the Monster Energy NASCAR Cup Series and Xfinity Series races on the 2-mile California track. The multi-zone rubber will feature a more durable compound on the tread’s inside two inches, with the outer 10 inches optimized for traction.
Goodyear’s update brings the right-side tire in line with the construction used at other speedways. The left-side tire is the same that both series used last season at Darlington Raceway, another track that features accelerated tire wear.
Sunday’s Auto Club 400 (3:30 p.m. ET, FOX, MRN, SiriusXM) will feature the full 2019 rules package, with reduced horsepower to a target figure of 550, increased downforce through larger spoilers, splitters and a wide radiator pan, plus ducts intended to alter the aerodynamic wake. Greg Stucker, Goodyear director of racing, said that the new package and a high-speed venue that places tire wear at a premium present challenges.
“First, with NASCAR’s new rules package and more downforce on the Cup cars, observing our minimum recommended air pressures becomes even more important," Stucker said in a release provided by the tiremaker. “Teams are always looking to add grip at Fontana, and one way they do that is by dropping the air pressures, particularly in the left side tires. While we have made some updates to our constructions over the past several seasons, low air can still cause problems. Going low on air causes the sidewall of the tire to over-deflect early in a run and weaken its structure, creating a potential problem later.
“Secondly at Fontana, you have a track surface that wears tires heavily. The fall-off is around three seconds a lap over the course of a fuel run, so tire management will come into play all day. Tire wear generally does two things for the fans — enhance the quality of the racing by creating more passing and bringing the pit crews more into play and emphasize the team aspect of our sport as teams take four tires every chance they get."
The construction update emerged from a tire test at Auto Club Speedway on Jan. 9-10. Defending series champ Joey Logano, Daniel Suarez and Martin Truex Jr. were the participating drivers, all using the updated 2019 rules package.
Here’s the tire info for this week:
Set limits: Cup: three sets for practice, one set for qualifying and 11 sets for race; Xfinity: eight sets for the event
Tire Codes: Left-side – D-4834; Right-side – D-4838
Tire Circumference: Left-side – 2,227 mm (87.68 in.); Right-side – 2,251 mm (88.62 in.)
Minimum Recommended Inflation: Left Front – 19 psi; Left Rear – 19 psi; Right Front – 45 psi; Right Rear – 42 psi