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Goodyear Fast Facts – Bristol Dirt


NASCAR Cup Series — Race No. 7 – 250 laps / 125 miles

NASCAR Camping World Truck Series — Race No. 5 – 150 laps / 75 miles

Bristol Motor Speedway (0.5-mile dirt oval) – Bristol, Tenn.

Fast Facts for March 26-28, 2021

Tire: Goodyear Eagle Dirt Bias Ply

Set limits:
Cup: 3 sets for practice, 1 set for qualifying race and 5 sets for the race (4 race sets plus 1 set transferred from qualifying);
Truck: 1 sets for qualifying race and 3 sets for the race

Tire Codes:
Left-side — D-3044;
Right-side — D-3046

Tire Circumference:
Left-side — 2,179 mm (85.79 in.);
Right-side — 2,248 mm (88.50 in.)

Minimum Recommended Inflation:
Left Front — 18 psi; Left Rear – 18 psi;
Right Front — 22 psi; Right Rear — 22 psi

Storyline – Dirty differences: There are three main differences between the Goodyear tire set-up NASCAR teams will run on the dirt at Bristol Motor Speedway this weekend and the one that these teams “normally” run on concrete or asphalt ovals.  First, these are bias ply tires — not radials — and are more compliant and able to envelope the irregularities of the dirt surface.  Second, these tires have a block-style tread pattern, not a “slick” or smooth tread.  The leading edge of the blocks bite into the dirt and the grooves in the tread help evacuate the dirt.  Third, while the size of this right-side tire is similar to what teams are accustomed to running, this left-side tire is significantly shorter to build in more stagger between the left- and right-side tires.  This tire is based on a dirt modified tire in Goodyear Racing’s tire line, though it has been widened out to 11 inches (from 10 inches on the dirt modified tire) to give the NASCAR cars and trucks more grip.

“Our tire set-up for Bristol this weekend has several obvious differences between what these teams are used to running throughout the NASCAR season,” said Greg Stucker, Goodyear’s director of racing.  “Goodyear started its transition away from bias ply tires in NASCAR in 1989, so none of these drivers have driven a Cup car on anything but a radial tire.  Bias ply tires are much more compliant than radials because they don’t have a belt package under the tread, making it more able to conform to an uneven dirt surface.  The other obvious difference between these tires and the ones teams run on Bristol’s concrete surface is the presence of a tread pattern.  All of our tires have a tread, but the concrete and asphalt tires do not have a tread pattern.  These dirt tires have a block-shaped pattern, both to bite into the dirt and evacuate it so the cars have grip.”

Notes – Bristol dirt tire set-up similar to what NASCAR Truck teams have run at Eldora: This is the first dirt track race in NASCAR Cup since 1970 and the first for NASCAR Camping World Truck Series teams since 2019 at Eldora . . . teams will be running two new Goodyear tire codes . . . while these tires feature the same block-style tread pattern that the Trucks ran at Eldora, both this left-side and right-side tire feature construction changes compared to those two tire codes . . . as on most NASCAR ovals one mile or less in length, teams will not run inner liners in their tires on the Bristol dirt track.

— Goodyear Racing —


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Contact: Mike Siberini, Goodyear Racing Public Relations – 704-905-3309 (C).