What is this plug and its function? This is off a B16 cylinder head and it is on the intake side behind distributor.



Thanks.

 

that is where you drill and tap the oil feed line when you build an ls vtec or crvtec (the mating of a DOHC vtec head to a non vtec 1.8 or 2.0l engine). looks like your head was used at one time in some ones build, or at least prepped for it, but then plugged off

 

You're correct! Thanks.