It must say DOHC VTEC if its vtec. There are 3 motors in 4th gen preludes in the USA. The one in the pic above is an F series motor. Its the same motor found in the 4th/5th gen accord. It comes in a prelude S. The Prelude Si motor is an H23 and it does not have VTEC either but it is a twin cam motor. Lastly the prelude VTEC is an h22a and it does have vtec and it says it. Look at the engine block right next to where the tranny bolts up. It will say "F22a or H23a or H22a" you'll know for sure then.