H22z1
 

I am debating on different motors to throw in my 98 integra ls. i was thinking on doing an ls/vtec with the existing block and a b18c head but i was wondering if just doing a complete swap using a prelude h22z1 would be possible instead? or would a lot of changes need to be made?

You would have to change everything, and h22 are not cheap. Just go with the ls/vtec.