If you want to check the clearance for when vtec engages plumb an air line at ~20 psi to the access port on the oil line that engages vtec. Then either jumper the solenoid or plug the outlet(the port into the head just inside and down from the vtec solenoid) and it should catch onto the high lobes when you rotate the engine over. Just remember that this is a dynamic system. You'd be surprised how much stretch there is in the connecting rods at high rpm