Originally Posted by Auto-X-ZTS
That is an inaccurate statement. OE LSDs are legal in stock class. There are certainly cars on the stock exclusion list (e.g. Cobra R) but that is due to limited production numbers, not equipment. Torsens, if OE, are perfectly legal.
While I can't speak to the Cooper, I can tell you about the Camaro.
In 96-97, Chevrolet released the 1LE package Camaro. 3:73 rear, Adjustable Koni Shocks (FROM THE FACTORY) pan-hard set up and heftier front suspension.
SCCA classed it in F Stock.
For me, driving a conventional Firebird, there was no competition.
That aspect of the rules...SUCKS.