[Paul Spotts]

I supply All Pontiac with the plug kits. The black plugs are a special 7/8 taper NPTF - the "f" is for fine thread. These were required on the early run of blocks and impossible to find. The machining was changed, not the quality of the plug. There is a special tap for those plugs, and I now use them in stock blocks - its 3/8 NPTF and should be coated (like TiN) for cast iron. Once my supply is done of the black plugs (I purchased a 1000 of the plugs), the kits will have standard 3/8 npt plugs. This also happened with the 1" pipe plugs in the back. The black plugs are actually called "dry seal, flush fit plugs" The fine thread and different taper allows the seal to take place in high pressure situations, not really applying to our usage. At least the pioneer 3/8 plugs are easy to get.

The brass plugs have some issues as well. These can be slightly porous sometimes and have threads that will allow the plugs to go into the block. I usually coat them on the inside and use either right stuff, grey permatex or brown permatex. There are choices with those as well. All Pontiac has a nice billet piece and I recently found an aluminum hex head pipe plug - but they stick out further and could have issues with certain headers.


I also changed the 1/8 plugs to external hex head - used to supply internal hex head and they could round out when removing plugs - Pontiac used external hex plugs as well (they always had great engineering)

So you can see I did a lot of research on the plugs when we tested the first IA2 block, but still changes go on. Its all part of the game.