A. The tire rule may be amended by bulletin.
B. The only tires approved for DIRTcar competition are the Hoosier: M-30S and M-60 compounds in the DIRTcar plated tire 26.5/8.0/15 or 27.5/8.0/15. The maximum width of the tire will be 9” inches.
C. The M-60 may be used as a right rear option tire only.
D. NO GROOVING allowed.
E. Siping permitted on M-30 and M-60.
F. Recapping of an approved tire is not permitted.
G. Any local track and/or DIRTcar official can confiscate any tire at any time and during any DIRTcar event to be evaluated and analyzed including verification using a tire durometer. Tires may also be submitted for further chemical analysis.
H. Defacing or altering any of the manufacturer’s identification markings, letters, words, numbers, on any tire will not be permitted.
I. Any alteration of tires may result in immediate suspension from all DIRTcar racetracks and/or events and/or penalties deemed appropriate by local track and/or DIRTcar and/or World Racing Group Supervisory Officials.
J. Tire softeners and/or chemicals designed to alter the chemical characteristics of the tire and/or the tire surface will not be permitted.
K. Bead locks will be permitted on the right side only.
L. Wheel discs shall be fastened to the wheel using a minimum of three (3)- 5/16 inch or (3) ¼ inch diameter magnetic steel hex head bolts.
M. The use of wheel discs with any other type of fastener will not be permitted.
N. As an option, a wheel cover with minimum of (5) five steel Zeus fasteners mounting points may be approved.
O. Only 8-inch DIRTcar approved and labeled racing wheels will be permitted. Wheels must not weigh over 30 pounds.
P. All wheels must be conventional one-piece magnetic steel and must be mounted with lug nuts. Aluminum, plastic and/or carbon fiber wheels will not be permitted.
Q. All wheels must be fastened to the hub with five lug nuts.
R. Wheel spacers are permitted. Wheel spacers may only be manufactured from magnetic steel or aluminum. Exotic, heavy metals are not permitted. Wheel spacers must not exceed one (1) inch in thickness. Wheel spacers must not exceed a 6-1/2 inch outside diameter.
S. Approved fastening (nut assembly) systems:
a. Keyser Manufacturing – Part #100 7-101.
b. Wehrs Manufacturing – Part # WM377A-312 Aluminum 5/16 / WM377S-312 Steel 5/16
c. Triple X Chassis – Part # SC-WH-7810 (for a 1” spring) / SC-WH-7820 (for a 1 3/8” spring)
d. Pit Stop USA Part #:
e. Smith Precision Products – Part # MC-516-18