2012 Solo Rule book, page 88, Street Touring Category, Section 14.10, subsection C:
C. The air intake system up to, but not including, the engine inlet may be modified or replaced. The engine inlet is the throttle body, carburetor, compressor inlet, or intake manifold, whichever comes first. The existing structure of the car may not be modified for the passage of ducting from the air cleaner to the engine inlet. Holes may be drilled for mounting. Emissions or engine management components in the air intake system, such as a PCV valve, or mass airflow sensor, may not be removed, modified, or replaced, and must retain their original function along the flow path.

Maybe they have canged it in the past 10 years. I just started racing at the end of last season. Per the rule book though you can change out the restrictive intake accordian pipe for a smooth hard pipe, as long as the MAF is not modified or removed.

 

This has been the most interesting and informative thread I have seen since I've been here, thank you all. Possibly a stciky, or placed with in a sticky?