318 viable, yes. 2002 no chance, with any real competition. 320, also no chance. Unless mid-pack with a well prepped car is viable to you.
In summary:
323 (E46): Heavy, not likely very fast in ITS, but we'll see what Irish Mike can do.
325 (E36): Still good in ITS with the SIR, underdog in ITR
325 (E30): Fair in ITS
318 (E36): So far, rare in ITA, but don't count on it up front
318is (E30): Same as above
325e (E30): Decent ITA car, at least in Florida
2002tii: Pitiful ITA car, might be decent if moved to ITB
318 (E30): Decent ITB car
320 (E21): Poor ITB car with 2.0L engine, even worse with 1.8L
2002: Poor ITB car
1600: ITC, never seen one run.
See the megasquirt topic for more detail on the 320.
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