[neon_rt]

The 2.5l is a Mitsubishi engine and has the same block and heads as the Mitsu 3.0l engines of the same year. There is a website (with associated shop) that specializes in removing the 2.5l and replacing it with a 3.0l in the Avengers and Sebrings. It is far less complicated than turboing and retains all of the factory computer and diagnostics. The 3.0l puts out about 210hp. They have done some 3.5l upgrades also.
If you still want to turbo your 2.5l, I would assume that the Mitsu 3.0l turbo setup would work for it. You probably need to buy a whole donor car from the junkyard (wrecked, but running) and move the parts over. You will need a piggyback controller to go with that. The piggyback controller allows the engine controller to run the engine as it normally would. The piggyback controller "hides" the turbo from the engine controller and then adds fuel and takes away spark timing to compensate for the Turbo.