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Pg:63 SCCA 2005 Solo Rules.
13.3 TIRES
Any tire which is OE on a car eligible for Stock Category may be used.
Non-OE tires must meet the following requirements to be eligible for
use in Stock category:
A. The tire must not appear on the following list, which may be
altered at any time by the SEB upon notification of membership.
No tire models are currently listed.
B. No tire models will be approved for competition during the rest of
the year after April 30 of each calendar year. Each eligible tire
model must meet all requirements of Section 13.3 by April 30, and
must continue to meet them thereafter. A tire model will normally
be determined by the designation in the Tire Guide. However, any
of the following changes or similar changes (as determined by the
SEB) will also be considered to represent a new model for eligibility
purposes, even if the designation does not change: change of
tread pattern at either full or partial tread depth; characterization by
the manufacturer or distributor of a tire as “new” after April 30.
A tire model which was previously allowed by these rules continues
to be legal until specifically disallowed. This follows years of
precedence on eligibility for discontinued tire models.
If a manufacturer reintroduces a tire model which was previously
discontinued, that tire will be considered a new model. Therefore,
it will have to meet the rules specified in SIIR Section 13.3 including
the April 30 introduction date.
C. The model of tire must be listed in a current or previous two years
of the Tire Guide and Tread Design Guide, or otherwise be ap64
proved by the SEB. The tire model must have Department of
Transportation approval.
D. Within each tire model, the sizes which are available must be
equally available to all competitors. Tire model variations differing
from standard specification, delivered only on a limited basis, or
only to selected competitors, may not be used.
E. No racing tire or recap (on any casing) may be used.
F. Each tire model must be sold in at least four rim diameters, with a
total of at least six sizes.
G. Tire must fit the allowable wheels and fender wells without modification.
H. Each tire must have non-zero measurable tread depth (i.e., points
where it is possible to obtain positive measurement values) as
described in Section 3.3.D . Tires may not have cord visible at any
time during competition.
