Crash listen,
ALL Civic EX's are VTEC
Look to the left of your valve cover, there is a little round cylinder thing about and 1.25 inches tall, that is your vtec solenoid, this is what kicks in your vtec. Trust me you have vtec.
For your exhaust, I also have the N1with piping from a muffler shop. Take it to a muffler shop and tell them to make you 2.25 piping from the catlytic converter all the way back to the muffler. They will know what to do.
Don't get 2.50 its too big of piping, you will lose low rpm power. 2.50 and up is only for turbo or heavy modified DOHC engines. Even I only have 2.25, look at all the performance parts I have.
One thing to note, without the resonator (the smaller muffler looking thing before the muffler), it is really loud. I saw in a Sport Compact Car ad, there is a place that sells just the cat back piping with the resonator for $129. I think its options auto salon or something. I think I'll buy that soon.
Smell ya later......