All Small Six Vacuum fitting for DODE carb spacer

[Mattsmall1972]

Hi all - I upgraded my head to a 1977 large log and I am running a small carb spacer (casting number DODE, see picture) to fit my Holley Sniper 1100. There is a vacuum line that I want to use for my PCV valve (circled in red).

The bolt that is in there now is about 3/8 inch, but it fits loosely and I think that the threads are NPT. I want to fit a brass hose adapter on it but can't figure out what the thread size is. Can anyone help me with identification of a fitting for this part? I have it installed already and really don't want to take it back off...

Thank you!

 

[frozenrabbit]

That port is not threaded from the factory, some one just put a bolt in there. That's the factory PCV vacuum port, no fitting.

 

[TrickSix]

I was just about to post the same thing. If you want a different size line, you could cut the nipple off and tap for pipe thread (maybe 1/4, maybe 3/8) so you could install a whatever size you want nipple.

 

[Mattsmall1972]

That port is not threaded from the factory, some one just put a bolt in there. That's the factory PCV vacuum port, no fitting.

So interesting, as there's definitely a thread in there. There is no nipple at all. I guess I'll just put a hose over it although I wish I could find an adapter.

 

[TrickSix]

This is what one normally looks like. Cast in nipple for I think 3/8 id hose, maybe 7/16. If there’s threads on the inside of the nipple a PO probably cut them, or maybe just from the bolt getting forced in. If the bolt screws into a threaded hole in the side of the spacer, depending on the size of the hole, tap for npt, probably 1/4 or 3/8. Then you can use a nipple sized for the PCV hose you’re using.

 

[TrickSix]

Whoops, I take that back. Was out in the garage so I grabbed this - a spacer that had a damaged cast in nipple. So I cut it off and installed this brass 3/8” hose barb. But I remembered wrong, the hole in the side of the spacer for this hose barb is only tapped out to 1/8 npt. 1/4 npt might fit but 3/8 would be too big.