vtech is a phone. vtec is in your honda.
the head isn't worth it, and unless you plan on spending way too much money for a motor that is either still slow(probably) or very not driveable (you talked to the right people, paid them lots, and run in a very restrictive nhra class), internals on the d aren't really the best idea. if you want a little power and a loud car, go the i-h-e route. ifyou want more for not so much money, research some low(6- eight) psi turbo (yes i said it) kits or a j-r supercharger.
or be smart, and swap in a b-series. a cable b16 (for your ef, cause it needs a cable tranny or an adapter to use a cable on a hydro tranny) can be had for around 1200 from a reputable shop like hmotors - talk to steve- and can be built with much better gains.
in short-
don't try to make na power with the d unless you are classed that way. i don't care what anyone says otherwise.
swap in a b-series if you want more power
low-boost turbos and superchargers are cheaper than n/a builds
this was all really fast and i'm tired. feel free to ask more questions or try to tell me why i'm wrong.
EDIT- JUST USE THIS->
http://www.honda-tech.com/zerosearch