Size of drain plug on pass side of block?


Mine is leaking and I am going to go to the zone and by a pet- cock to put in there and need to know what size it is. John at John's Performance said it was 1/ this correct? ;)
ANd be careful with that...1/8" NPT, contrary to common sense, is NOT 1/8" in diameter. Make damn good and sure you are purchasing 1/8 NPT (National(?) Pipe Thread). You also do not want the British pipe thread size.

You will prolly have 2 or 3 petcock styles to choose from...some are radiator-style petcocks, others are intended for air bleeding (but work fine).