1969 NASCAR International Stock Car Racing Rule Book NASCAR Grand National Championship Circuit Section 20-27 -- Tires

a. No knobs, powergrip baldies, slicks or drag tires permitted. No cross grooving allowed. Standard treads only. Racing rubber permitted.

b. All four tires must be the same size as to actual measurement, and must be of the same make and the same tread design.

c. A measuring device will be used to determine maximum size of tire. Tires can not exceed maximum side wall measurement of 12.20 inches plus .15 tolerance at 60-pound pressure, mounted on 9 inch rim. Maximum allowable tread width 10 inches. New tires will be selected at each NASCAR event by qualified NASCAR technical inspectors for measurement to be made with calipers. Tires to be inspected must be mounted on a 15" wheel having a 9" rim width. Sixty (60) pounds tire pressure will be required for the measurement.

d. Recaps must be approved by organizer, and recaps will not be permitted on any track one mile or over in size. Width of any recap tread cannot exceed width of original new tread for that tire and the maximum retread width is 10 inches. When retread tires are used, all four tires must be the same width and tread design.

e. Same type tread and grade rubber must be available to all contestants. Any deviation from this rule must be approved by the NASCAR Technical Director.

f. Stock racing tires, with inner safety tires, compulsory on all NASCAR super-speedways and other specified tracks. Violation of this rule will result in fine and/or disqualification of the car.

g. Immediately following a qualifying run, wheels and tires from a qualified car will be impounded by NASCAR inspectors and will be returned for remounting when cars are prepared for the start of the race for the purpose of having contestants start a G. N. on the same tires used for qualifying under the following conditions:

(1) Wheels and tires may be taken from all 1st and 2nd day qualifiers and the NASCAR Technical Director is authorized to impound any other wheels and tires he may select. All wheels and tires must be remounted in position from which they were removed.

(2) No contestants will be permitted to make unauthorized tire changes prior to completion of first lap of race.

(3) Contestants requiring or requesting a change of 4 tires will forfeit their qualifying starting positions and will be required to start in the rear of the field.

(4) In the interest of safety, the Technical Director may approve the change of one (1) tire per side without a starting position penalty provided the replacement tire carries the same manufacturer identification as the tire used for qualifying.

(5) Contestants will be permitted to re-balance tires and remount or change safety shields under supervision of NASCAR inspectors.

(6) Tire manufacturers must furnish the NASCAR Technical Director with tire identification markings prior to qualifying and contestants must notify the Technical Director of intended usage of previously approved tires for qualifying runs or in the race.