I know what everonye is about to say... "search"

Well, I searched and searched... and I found everything but what I need to know.

What size plugs do I need to plug my stock manifold???

In searching.. I saw someone mention 3/8... I bought them... too big. Then I came home and searched more... someone said 1/4. I went to Home Depot, returned the 3/8 and bought 1/4... the thread doesnt fit. I know our cars are metric... someone help me out please.

(PS: After this is done I will make a tech article that is a little more compleete)

-Jim

 

I assume your referring to the air manifolds? IIRC, theyre 1/2" NPT pipe caps. Measure the OD of the fitting on the air manifolds to be sure. Theyre definatly NPT threads, though. The dimension you measure will be ~2x the size that you need. I dont know what size youd need for the actual manifolds. Those probably arnt NPT threads. Youd have to bring the fittings in with you.

Edit, yet another solution is to drill and tap for NPT plugs if the threads arnt NPT. Probably 1/8" would work. I did this on some headers and the tapered thread plugs seal real nice.

 

What are trying to plug? There are 2 possible spots. If you're keeping the AIR tubes and just plugging the diverter valves (one on each side), I can't remember what size it takes.

If you completely removed the AIR tubes, and are looking to plug the holes in the manifold (it sounds like your doing this, but just making sure), than 1/4" NPT pipe plugs will work. That's exactly what I used when I did mine.

You can see them in this pic:

 

yes, i'm trying to plug the manifold. I have 1/4 in. brass, square head plugs that I got from Home Depot. The plug only threaded in a few turns... I didnt try to tighten it more because I didnt want to strip it out. May be I cross threaded it... I'll have to try again tomorrow. Thanks for the help.

-Jim