The Basics on Brake Upgrades

[ilikerice]

I don't know where you got that from ez, but It clearly states in the SCCA book under
82 — 2015 SCCA® National Solo® Rules
14. Street Touring®
14.6 BRAKES
A. Non-standard brake rotors may be used provided they are of equal
or larger dimensions (diameter and thickness) and made of ferrous
material (e.g., iron). Thickness includes the individual plates of a
vented rotor, as well as the overall dimension. The diameter for replacement
rotors is measured at the minimum outside dimension.
Aluminum rotor hats are allowed. Cars originally equipped with solid
(non-vented) rotors may utilize vented rotors. Cross-drilled and/or
slotted brake rotors may be fitted provided all such voids are within
the disc area and comprise no more than 10% of that area. Brake
calipers and mounting brackets may be replaced provided they bolt
to the standard locations and the number of pistons is equal to or
greater than standard. A functioning emergency brake of the same
type, operation, and actuation as OE must be present. Drum brakes
may be replaced with disc brakes of a diameter equal to or greater
than the inside diameter of the standard drum. Such conversions
must be bolted, not welded, to the axle/trailing arm/upright and must
include an integral, redundant emergency brake. Changes to backing
plates/dust shields/brake lines to accommodate these changes
are permitted but may serve no other purpose.

I don't see anywhere it talks about rear drums...

Street Prepared
15.6.E. Drum brakes may be replaced with disc brakes. Disc brake rotors
for such a conversion must be equal to or greater in diameter than
the inside diameter of the standard brake drum. Changes to backing
plates/mounting brackets/brake lines to accommodate this change
are permitted but may serve no other purpose. Drum-to-disc brake
conversions must be bolted, not welded, to the axle/control arm/upright.

You are correct, I do not see yaris listed in any part of the Street Prepared cars that are listed. So it would go straight to SMF.