ive had a 04 civic ex for about a year in june, and i just got in to this whole honda thing (i used to have a 2004 WV R32) and the hondas are fun corner huggers but in the hp part they lag, so i wana know whats best for upgrades.
i wana stay all motor.
so far i got K&N intake, magnaflow exhaust, and DC sports header. tranny swap is soon to come cuz i bought an auto like a dumbass.
what else can give me some pep for the single cam?
K20 or B16 may come soon.
it all depends on the amount of money you wanna spend and what you wanna accomplish. B swap is not legal in our 7th gens due to the age of the engine. Its older than our chasis so you may run into a problem down the road if you do that. as far as swaps the only engin (at the moment) that can be legally swaped into our cars is the K series (K20, K24 etc.)
If your looking into building the engine you have the D17a2. The best bang for your buck would be Nitrous, Nitrous Express, NOS, and ZEX from what I hear are very good..as long as you get the wet system.
If thats not an option you can go all out with rebuilding the engine, port and polish, individual throttle bodies, upraded ecu, tranny, injectors etc..but this will not produce that much HP compared to the amount of $$ you will spend.
Basically to get power and stay NA..swap is the only answer
If you dont have enough funds right now just concentrate on handling as 7th gen is awesome to drive when equiped w/ a good suspension set up.
Check out this guys build up on the D17 just in case you have not seen it yet pretty amazing..but rember this guy probably has about 18-20K invested into it
http://honda-tech.com/zerothread?id=1772982
hope this helps and good luck