I didn't get into third at all. Our courses are setup on the small side.
I have been looking through the SCCA rulebook and I can't find anything about gearing except the stock class which states all differential ratios must be standard. Street Touring and Street Prepared don't state anything about differential gears. Street Modified says drivetrain and related components are unrestricted except for the listed items, none of which mention diff gears. Prepared specifically states that any rear ratio is allowed.
ST and SP don't specifically mention differential gear restrictions because the rules are built upon the stock category?
I love the gears from a driveability standpoint.
It is kind of confusing.
For all Solo rules, unless it says you can, you can't.
For SP, update and backdate to items from cars on the same line as yours are allowed. There are some restrictions about whole components, but for axle ratios that doesn't matter.
So, you can update or backdate to the 3.55 gears that were offered in the Cobra R or Mach 1 or whatever model had the best ratio.
I don't know how ST works, except there is no update/backdate so it is not allowed.
Unrestricted in SM means just that, completely unrestriced. You can put a 9 inch or whatever in that case.
Same with Prepared.
And I already stipulated to agree that the rules suck, are written by idiots, SCCA sucks, etc, so no need to go there.
Just go have fun, you can have plenty and be locally competitive in any of the classes mentioned.