Do you have a tach? Does it work? Vtec is not ran according to your speedo, but your rpms. Your Vtec will kick in when the ecu recieves the notice from the tranny that your engine's rpms is at the level that requires vtec. For example, an EG EX or SI has Vtec kick in when your tranny lets the P28 know that your engine's rpms is at 5,500.