Ugh, class changes. I've run STX for exactly 1 event this year, feel bad that I got my SCCA membership and then only went to 1 event. I enjoy it more with friends, haven't really found any in the autox scene up here since all my buddies moved away or sold their fun cars.

In reference to not being able to change intercoolers and boost piping, I recall reading in the rules that changing the intake system up to the throttle body was STX legal in 2013. Just search for throttle body in the STX section.

 

The rule reads throttle body, carburetor, compressor inlet, or intake manifold, which ever comes first, so charge pipe/intercooler changes are not legal for STX. SCCA definitely has some oddities with their classing rules, but unless you're going to Nationals or live in a place with strict local events you can tend to get away with a lot.

 

Ah, I missed the part about the compressor inlet. They lump STX and STU together at my local events, I get murdered by WRXs and Evos.