Originally Posted by Bl@ck
to answer your question.. yes you do. federal law mandates that if you swap an engine into a car the engine being installed must be newer than the car. in short, you can't swap in an engine from a '94 prelude into a '95 accord, etc...
Well, there's loopholes. It depends where you live. If you don't have emissions testing like here in NH, nobody will know the difference.
As far as OBD emissions, yes, OBDII would be the easiest swap. You can do an OBDI but plan on spending some time converting all the harnesses.