hello!
this topic is pretty old...many other ppls ask about it and we reply but again i reply
Honda Civic Exi is 1500cc with PGM-fi(No Vtec tech in engine)
Honda Civic Vti is 1600cc with PGM-Fi + Vtec....thats y called Vti
Honda Civic Vti Oriel is same like Vti Pgm-fi+Vtec but it include some additional things + Sunroof.....
and now u ask what this all pgm-fi and vtec is so
Pgm-fi=Programmed Fuel Injection like Efi...
Vtec=Honda's engine tech which is made for better performance and good avg of engine...
Thanxxx