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Hey all , i have a OBX mid-length header on my neon, and it has been real good, but the flange is warped and has been since i got it, but even with a double gasket it leaks.

Has anyone ever flattened a header flange before?? I have heard of cutting the flange around the runners so I can tighten it down in sections.

It is stainless, so it is rather malleable i presume. Anyone with any suggestions would be appreciated.
here are pics of it.

THIS IS WHAt I thought might help. look at the 2 different pics.

Have the flange machined flat, and just cut relief cuts between the runners. No point in removing that much material.

for starters, i relocated the topic...
For seconds, why did you wrap the headers?
The rumor I hear is if you wrap the headers, it will cause problems down the road, whether thats true or not I honestly don't know...
I also hear wrapping the headers is a great advantage, that is also a rumor I heard.....

A machine shop should be able to mill it flat for you. OBX is cheap shit, so I'd expect stuff like that.

Stainless is a bitch to machine so it may cost a little more than mild steel or aluminum to have it done. Cutting inbetween the tubes with a hack saw is free, but if it still leaks then it would be near impossible to mill the surface without welding it back together, which could make the warping worse. If it was me I'd hacksaw it and go. When (if) you get another one check it with a straightedge before installing. If it isn't good then return it. At the vendor's expense of course.

PSH!!! Try returning anything to OBX. They're based out of china. Really hard to work with.

It isn't really even machine work, like on a head surfacer with a rotating head. The machine shop will slap it down on their ~12x36" or so belt sander for a minute or less, charge you a half hour labor and you are done.

Cutting it will probably work, but I'd hate to do it.

I guess you could cut inbetween them, the stock manifold, and the OBX short tube are all seperate, but it makes it a B to put it on.

^^^^^^True, but if we were talking the ideal soulution it would be a lawn ornament! Belt sanding would work, but the quality is only as good as the person holding it. you could get the surface out of square real easy if not careful: hate to see it at the wrong angle. It really depends on how much needs removed. With less meat, it will be sorta like turning warped rotors...

occasional demons wrote:quality is only as good as the person holding it

Good point. I forget about operator error.
The local place here does cast manis all the time on the belt, and would be careful to square it up, but there is always that other guy.

BlackRoseRacing wrote:for starters, i relocated the topic...
For seconds, why did you wrap the headers?
The rumor I hear is if you wrap the headers, it will cause problems down the road, whether thats true or not I honestly don't know...
I also hear wrapping the headers is a great advantage, that is also a rumor I heard.....

I wrapped it to keep the temp down, and if you don't you will loose you shifter cables to melting. and it looks stylish and no one else here TO MY knowledge has done it before..

I know OBX sux, but again I was the first person to try this LENGHT of OBX, the header is actually amazing except for the flange thing.

What do you guys think , if I were to cut reliefs into the header, then using a square large belt sander slowly milling it down .. ?

thats what i will prolly end up doing, be a guinea pig for it .lol

If you mean cuttting reliefs as in separating the tubes so each has it's "personal" flange, don't do it till after you've sanded down the surface or they will flex independently of each other and you will have a lawn ornament! If you get the surface flat then I don't think there will be a need to separate them. Like invujerry said it would be a B to install: each flange would want to do it's own thing so the tube would have to be positioned to get the holes to line up due to the stresses being free from one flange. Hope that makes sense!

occasional demons wrote:If you mean cuttting reliefs as in separating the tubes so each has it's "personal" flange, don't do it till after you've sanded down the surface or they will flex independently of each other and you will have a lawn ornament! If you get the surface flat then I don't think there will be a need to separate them. Like invujerry said it would be a B to install: each flange would want to do it's own thing so the tube would have to be positioned to get the holes to line up due to the stresses being free from one flange. Hope that makes sense!

I'm not the most knowledgeable person in this field but for some reason grinding it down just seems wrong to me. how much is the flange off by?

have you thought of using a torch until it gets pretty damn hot (pre-glowing) and quickly bolting it up? Maybe the bolts will push the flange into proper position.

kevo wrote:I'm not the most knowledgeable person in this field but for some reason grinding it down just seems wrong to me. how much is the flange off by?

have you thought of using a torch until it gets pretty damn hot (pre-glowing) and quickly bolting it up? Maybe the bolts will push the flange into proper position.

And then maybe weld to the head! Or the bolts too! I don't know if I like that idea. I'd be up to find a machine shop to mill it down or the belt sander on VERY fine grit.

invujerry wrote:

kevo wrote:I'm not the most knowledgeable person in this field but for some reason grinding it down just seems wrong to me. how much is the flange off by?

have you thought of using a torch until it gets pretty damn hot (pre-glowing) and quickly bolting it up? Maybe the bolts will push the flange into proper position.

And then maybe weld to the head! Or the bolts too! I don't know if I like that idea. I'd be up to find a machine shop to mill it down or the belt sander on VERY fine grit.

was just an idea thrown around. It just sounds to me like its pretty warped if he has two gaskets and its still leaking.

I had a blackdog that came in the mail like this (second hand). Of course it had to be saved!
One visit to a shop that did racecar fabrication and all was well again.