you cannot use a Z6 VTEC camshaft with a non-VTEC head - the heads are completely different - if his engine is the SOHC ZC non-VTEC, then all of the parts are the same as a D16A6 - if it is VTEC, then all of the parts are the same as a D16Z6 - here is a picture of a SOHC ZC VTEC - you can tell it is VTEC by the valve cover (this one has been painted red, typically they are black) and by the VTEC solenoid where the yellow arrow is pointing - most SOHC ZC VTEC engines have a serial number beginning with the number '7' (like second picture) - most that are non-VTEC will have serial number beginning with the number '3' or '5' - of course, if he bought the car with the engine already in it, someone could have swapped a VTEC head onto the non-VTEC block
