I'm getting ready to go racing in the FM I bought a few months ago and have been practicing and testing in. I plan to run with SCCA/CalClub and HSR West in SoCal, and Formula Car Challenge in NorCal.
I noticed that the June FCC event at Infineon runs with NASA, and has a $650 weekend entry fee. But if you race with NASA in one of its modified street car classes, the weekend fee is only $349. Why the $300+ differenece? Track time is the same.