NASCAR Cup Series — Race No. 9 — 250 laps / 133 miles
Bristol Motor Speedway (0.533-mile dirt oval) — Bristol, Tenn.
Fast Facts for April 7-9, 2023

Tire: Goodyear Eagle 18-inch Dirt Radial

Set limits: 3 sets for practice, 1 set for qualifying and 6 sets for the race
(5 race sets plus 1 set transferred from qualifying)

Tire Codes:
Left-side — D-5164;
Right-side — D-5166

Tire Circumference:
Left-side — 2,297 mm (90.43 in.);
Right-side — 2,327 mm (91.61 in.)

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

Storyline — Goodyear dirt radial tire simulates bias ply feel: Goodyear introduced its dirt radial tire for Cup cars at the Bristol Motor Speedway dirt track last season after running a bias ply tire in NASCAR competition prior to that.  In general, bias ply tires are more compliant and able to handle the irregularities of a dirt surface better.  Goodyear designed its dirt radial to behave similar to a bias ply, but with the advantage of having more consistent sizing from tire to tire that a radial provides.

“Having to move to an 18-inch bead diameter tire for the 2022 season, it gave us the chance to switch the Cup cars to a radial tire for the Bristol dirt race, where we had been running a 15-inch tire on dirt in NASCAR competition up until then,” said Greg Stucker, Goodyear‘s director of racing.  “Radial tires provide more consistency in sizing, but we didn‘t want to lose the bias tire‘s ability to handle the dirt surface.  What we did was design the tire‘s construction to be more compliant, making it ‘feel‘ like a bias ply.  While we maintained a block-style pattern with the radial, we adjusted it slightly to help grab the dirt even better, based on what we‘ve learned over time.  At the same time, we also adjusted the tread compounds to be more heat and wear resistant.  Based on the success of the 18-inch tire last season, we decided to move the Trucks to a 15-inch radial for this season.”

Notes — Cup cars back to Bristol on radial dirt tire that had its debut in ‘22: Being on the 18-inch bead diameter tire, NASCAR Cup teams will run different Goodyear tire codes than those in the Truck Series on the Bristol dirt track this week . . . for Cup, this radial tire with a block-style tread pattern debuted in this race last year . . . with this 18-inch tire, and its lower profile sidewall, Cup cars will not run inner liners in any of their tires in 2023.

NASCAR Craftsman Truck Series — Race No. 6 — 150 laps / 80 miles
Bristol Motor Speedway (0.533-mile dirt oval) — Bristol, Tenn.
Fast Facts for April 7-8, 2023

Tire: Goodyear Eagle 15-inch Dirt Radial

Set limits: Truck: 4 sets for the event

Tire Codes:
Left-side — D-6154;
Right-side — D-6156

Tire Circumference:
Left-side — 2,248 mm (88.50 in.);
Right-side — 2,278 mm (89.69 in.)

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

Notes — Trucks move to new dirt track radial: NASCAR Craftsman Truck Series teams will be running two new Goodyear tire codes compared to what they ran on the Bristol dirt track in 2022 . . . the changes mirror those that Cup Series teams had rolled in last season, just in a 15-inch version — (1) a switch from bias play to radial and (2) a slight modification to the block-style tread pattern, now with beveled edges to better grab the dirt . . . as on most NASCAR ovals one mile or less in length, Truck teams will not run inner liners in their tires on the Bristol dirt track.

— Goodyear —

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