Monster Energy NASCAR Cup Series — Race No. 5 – Auto Club 400
NASCAR Xfinity Series – Race No. 5 – NXS 300
Auto Club Speedway (2.0-mile oval) – Fontana, Calif.
Fast Facts for March 16-18, 2018
Tire: Goodyear Eagle Speedway Radials
Cup: 4 sets for practice, 1 set for qualifying/start of race and 10 sets for race;
Xfinity: 8 sets for the event
Left-side — D-4754;
Right-side — D-4658
Left-side — 2,227 mm (87.68 in.);
Right-side — 2,245 mm (88.39 in.)
Minimum Recommended Inflation:
Left Front — 19 psi; Left Rear — 19 psi;
Right Front — 45 psi; Right Rear — 42 psi
Storyline – Auto Club puts an emphasis on tire management: Auto Club Speedway has one of the more worn track surfaces on the NASCAR circuit. That puts a premium on grip on the two-mile speedway, which has come even more into play over the past several seasons as NASCAR has reduced the downforce in its aerodynamic package. As teams try to gain grip to counterbalance that, demands are often placed on the left-side tires as teams go below the recommended air pressure of 19 psi on that side of the car. Goodyear has continued its development of a robust left-side tire design, with a compliant sidewall that has become the standard on speedways. In fact, we return to Auto Club for this race with a new left-side tire that lines it up with what is run at other big tracks like Indianapolis Motor Speedway. Auto Club’s track surface will generate more than three seconds of fall-off over the course of a run so teams will hope to take tires at every opportunity. That means tire management and pit stops will be important all race long.
“Fontana has become quite a challenge from a tire perspective,” said Greg Stucker. “On the one hand, you have a surface that wears tires to the tune of three seconds of fall-off during a run. That means that tire management will be at a premium, and that always adds to the quality of racing by creating more passing. On the second hand, teams always look to find more grip at Fontana, and sometimes they do that by dropping the pressure in their left-side tires. While we have made some adjustments to our left-side over the past several years, low air can cause problems. Air pressure provides strength to a tire, and low air can cause the sidewall to over-deflect early in a run and weaken its structure, causing a problem later.”
Notes – Goodyear returns to SoCal with new left-side tire: Teams in both the Monster Energy NASCAR Cup and Xfinity Series will run the same tire set-up at Auto Club Speedway this week . . . this is the same multi-zone tread right-side tire these teams ran at this track last year, but with a brand new left-side tire . . . this right-side, being a multi-zone tread tire, features two distinct tread compounds on the same tire — one for heat and wear resistance on the inboard two inches of the tread (Endurance Zone) and one for grip on the outboard 10 inches (Traction Zone) . . . compared to the left-side these teams ran at Fontana last year, this year’s version features a construction update to bring into line with what is run at other speedways . . . as on all NASCAR ovals greater than one mile in length, teams are required to run liners in all four tire positions at Auto Club . . . air pressure in those inner liners should be 12-25 psi greater than that of the outer tire.
— Goodyear Racing —