More power in a prelude?

alright. im trying to get my hands on a gen 4 lude near my house. im not sure if it's s si or vtec. i was wondering, in case it isn't vtec with the h22a, what other engine can i put in it for maximum power? i was thinking 6cyl, maybe the GTR engine. or if it doesn't have the h22a, should i just buy one from JDM. thank you