Not a Mopar, question for header gurus

[MopaR&D]

So this is completely unrelated to Mopars but my buddy is building a 2.5L GM 4-cylinder to swap in his Miata and bought these headers. He's concerned about the lack of welds on the inside of the tubes to the flange, I said it's probably not a big deal but what do you guys think? Figured I'd ask here since FABO has so much collective engine-building knowledge and everyone is a straight-shooter here.

 

[RustyRatRod]

how can anybody know anything about that without seeing the outside where the tubes meet the flange?

 

[Ddaddy]

how can anybody know anything about that without seeing the outside where the tubes meet the flange?

Yep...the tubes must be attached somehow. If the external attachment is reasonably solid, no issue. If not, big issue.

The quality of how it’s built is more important than the way it’s built.

 

[MopaR&D]

Yep...the tubes must be attached somehow. If the external attachment is reasonably solid, no issue. If not, big issue.

The quality of how it’s built is more important than the way it’s built.

I don't have pics but I saw some of his, the external welds are really nice, he got a good deal on them even though the brand is generally considered higher-end for those cars. "Goodwin Racing"

 

[Bewy]

I made my own headers out of SS, & no welds inside. All outside, been fine for 15 yrs.

 

[diymirage]

oh come on
look at the thickness of the flange, and then look at the depth of the tubes

i would say those tubes are recessed about halfway into the flange

and i can see penetration on about half of them, especially the back tube in this picture

i would run em

 

[MopaR&D]

Cool thanks guys! That answers my question, I'll give my buddy a link to this thread.

 

[pishta]

Those flush flanges are way better than the "ground O-ring" jokes of Hooker that bend the flanges when they are cranked down! Run 'em.

 

[RustyRatRod]

oh come on
look at the thickness of the flange, and then look at the depth of the tubes

i would say those tubes are recessed about halfway into the flange

and i can see penetration on about half of them, especially the back tube in this picture

View attachment 1715714399



i would run em

"Oh come on" so who are you now, Biden? Lemmie tell you somethin smartass. I'm not going to give anyone advice anymore unless I can see the whole picture. Literally and figuratively. Too many variables. That's somebody else's money we're talkin about here.

 

[yellow rose]

"Oh come on" so who are you now, Biden? Lemmie tell you somethin smartass. I'm not going to give anyone advice anymore unless I can see the whole picture. Literally and figuratively. Too many variables. That's somebody else's money we're talkin about here.

Yep. From what little I can see, I’d weld up the inside of the ports to get rid of that sharp edge or grind it out of there if you can. But how can you say for sure with what little we see???

 

[rumblefish360]

With the use of the all seeing crystal ball.

(If anybody see’s rustyratrods, PM him for his address!)

 

[MOPARMAGA]

I have a set of headers on my dakota r/t they're not welded inside, just outside flange & they're fine. But the rest of my exhaust is ****- T.