engine swap in 95 civic cx NEED MORE POWER!!!!!!!

I have a 95 civic cx with a 1.5 8 valve is it wort while to swap in a 16 valve 1.5? Will i have to change the ecm? how much horse power will it gain? I already have this engine. Torn apart on my work bench ready for a rebuild. The 8 valve is gutless. Put on intake, exhaust removed a/c. Help need more power any suggestions will help. How much power is the 1.5 16 valve capable of? FROM VERMONT