I have a 98 Cutlass (TCV)...
Current upgrades to engine 1998 3.1 3600 V6
*Supercharger*
*Turbo*
*Zex Nitrous System*
*Intake*
*Grounding Kit*
*upgraged Throttle body*
*MSD ignition system*
*Ported Intake*
Hope that answer your question about how upgradeable the 3.1 is.
