I am considering using the Dougs headers on my 67 Barracuda the has the 74 A body spool mount K member . I understand from posts I have read that they will work with this K member . My question now is are the face of the flanges at the head flat ? I don’t like to use gaskets , and I prefer to install with high temp RTV. I have had great success on the flat flanges , but not as well when they have the raised bead . Also are the flanges 5/16 or 3/8 thick ? Have you had good experience with them ? Thank You !

make sure to cut the flanges between each exhaust port, and drill one hole on each tube section two sizes larger than they are at present.
this will make sure the pipes stay sealed, as it allows slight movement between heat up and cool down.
i stole this idea from member Mr. P Body at least 15-20 years ago, and it just flat works, no matter what gasket or sealing goo a guy wants to use.
this even works on the cheesy 1/4" flange tubes.
of course you want to make sure the raised bead or flange itself is relatively flat. a light dressing with a belt sander or da sander will work for that.

^^^ Yup, I've been doing that for decades, and never have warped flanges or header leaks.
Not only cutting the flanges, but cutting away the non-sealing flat stock between the ports.
Sometimes improves access, always looks more professional.
I'd bet it's even more important on the thinner flanges.
Also studs wherever possible.

ah, yes. as said, use the studs !
i forgot to mention that ! thanks for that reminder !
and if a normal size nut causes wrench or socket interference with the tube, check mc master carr for reduced hex flange nuts.

I have a set of D453s on my shop wall, never installed so I can't say what kind of luck with them.

They Mic out at around .400, so actually thicker than 3/8 but some of that may be the ceramic coating.

They do have a welded bead on the head mating surface. It is wide compared to other headers I've had, and looks like it was machined flat not just ground down.

I have D 452's on my Savoy and they have a large bead like posted above and I used the gaskets that came with them and they have been in there for about ten years and still quiet with zero leaks. I have seen pics of the D 453's and they look like the same type of flange weld job as mine. I would use the gaskets glued on with trim adhesive like I did mine and you should be OK

Gus

Thank You for info !

I saw a bunch of threads on 453 at Abodiesonly and they say thet work fine with what you have.
I was looking as might swap to them from my Hooker Super Comp. For 2 reasons

1) The Hookers hang low and the 453 do not and still clear all.thr stuff.
And 2) I do not like where the collectors end up.

I have looked and did not see how the 453 collectors are.
Was hoping the collectors come out where the factory put the headpipes in the crewmember. As I want the pipes tucked in the same place they were with the manifolds with the Hookers you have to go low and put a Big Woop De Doo at the collectors
Sorry if I highjacked your thread Ron.