im thinking my 2.2 is on its last legs, and i wanted to go to a 2.5L dohc but im not sure what is involved with making it work i figure it would bolt right in, but im concerned with the wiring
Wiring might be complicated, and the SOHC-DOHC will probably render some of your hoses useless. You might be better off finding a SOHC 2.5 if you are going that route. I'm not the expert on N/A stuff though, so I'll shut up now and wait for some of the experts to show up.
It was fairly Easy to Go 2.5DOCH to 2.5Sohc, so it might not be too hard. I had to switch the wiring plugs for the injectors, TPS, and a few other sensors, and I had to make a custom IAC setup, but that's cause I put a MAP based motor in a MAF based car. I'm just not sure how well the 2.2 ecu will run the 2.5