Anyone have a lathe and willing to help?

[Tooljunkie]

RRR has a point. That is an unusual thread in an intake. Would like to see the hole in intake,as well as the threaded end of the plug.
It wont be inverted flare in the intake as typically an adapter is threaded into cast iron.

 

[RustyRatRod]

RRR has a point. That is an unusual thread in an intake. Would like to see the hole in intake,as well as the threaded end of the plug.
It wont be inverted flare in the intake as typically an adapter is threaded into cast iron.

S'what I been tryin my damndest to tell um.

 

[Tooljunkie]

S'what I been tryin my damndest to tell um.

3/8 npt is close to 5/8-18.
Rob is correct.
3/8 pipe thread is 18 tpi.

 

[YY1]

What intake is the OP using?

 

[j_anderson]

What intake is the OP using?

part number 4323352
"manifold was used on 360 dodge trucks from 1985 thru 1988"


Here is where I asked the forum for info on the manifold.

 

[diymirage]

if this were me (and i dont have a dog in the fight)
i would spend the 37 cents on a 5/8-18X2 bolt and see how far it will bolt into that hole
then post a picture here before to at least put this thing to bed...before someone else end up spending their time and effort on what may never work

 

[j_anderson]

if this were me (and i dont have a dog in the fight)
i would spend the 37 cents on a 5/8-18X2 bolt and see how far it will bolt into that hole
then post a picture here before to at least put this thing to bed...before someone else end up spending their time and effort on what may never work

Already working on a solution. There is no fight here.

 

[diymirage]

Already working on a solution. There is no fight here.

im not talking about a fight
im talking about a half a dozen guys who know what they are doing and are giving you information that doesnt match what you are seeing

if it were me, i would want to verify that information because
A) i might be wrong (wouldnt be the first time)
B) it shows im willing to listen to these guys, and even if i dont need them to see this project through, i might need them for the next one, and this is a simple way to show them i am listening to them


but like i said, thats what i would do

 

[YY1]

Sometimes SAE bolts will thread into fittings, but they only go in a few threads.

What's "above" the contact threads will be loose and what's below the threads won't allow the bolt to go any further.
Sure you can force it and get a couple more threads, maybe. But now you still only have three or four threads making good contact and now the pipe fitting treads are ruined.

...and a leak is very likely

...and now the plug you removed won't seal, either.

 

[j_anderson]

im not talking about a fight
im talking about a half a dozen guys who know what they are doing and are giving you information that doesnt match what you are seeing

if it were me, i would want to verify that information because
A) i might be wrong (wouldnt be the first time)
B) it shows im willing to listen to these guys, and even if i dont need them to see this project through, i might need them for the next one, and this is a simple way to show them i am listening to them


but like i said, thats what i would do

Thank you and everyone for your input and advice.

Sometimes SAE bolts will thread into fittings, but they only go in a few threads.

What's "above" the contact threads will be loose and what's below the threads won't allow the bolt to go any further.
Sure you can force it and get a couple more threads, maybe. But now you still only have three or four threads making good contact and now the pipe fitting treads are ruined.

...and a leak is very likely

...and now the plug you removed won't seal, either.

The plug was sealed with tape and was a nice, fit when removed. There are 1/2" worth of threads on the plug and the same amount of threads in the port.

Having said that, I am having a piece made with both thread types.

Again, thanks to everyone for your input.