you have a 1th gen civic? i never heard of those. Do you mean a 1st gen civic? lol i'm just bustin' your balls so don't worry.
I'm not too familiar of what can be done to a 1st gen but i'm sure the possibilities are endless. My guess is the current motor is carb'd so any swap you'd decide to do, you'd have to change over to fuel injection.
Go search and look in the FAQ, there might be something there for you. goodluck.