I have a friend that has a supercharged (non-stock) 06 Mustang GT (4.6L) with an air-to-water intercooler.  Is there a class for him?? I assume he also has changed his lower control arms and suspension geometry as I have, so that would put him at least in C-Prepared as I am.  The big question concerns his intercooler. 

I couldn't figure out if it was allowed even after reading the regs many times.  15.10 C. 3. says:  Air-to-air CACs and radiators for air-to-liquid CACs must be cooled only by the atmosphere, except for standard parts"  ... which seems to indicate that and air-to-liquid intercooler is allowed at least in some classes.

John