Warped exhaust manifold. Can it be fixed?

[Schwamm]

I took my exhaust manifold off and had it welded because it had cracked, but I realized it is not flat anymore. It's not even close. You can lay a straight edge across it and see a big gap on one end. I have stripped out two of the bolt holes going into the head now and I think this might be why.

I have another manifold I purchased that is starting to crack on top and by the o2 sensor hole that has not been welded, but it is only slightly warped. Can these manifolds be honed down? How far?

I'm trying to avoid buying a very expensive aftermarket manifold but these stock ones are killing me...

 

[Preferio]

Yes, have it planed by a machine shop. That's the only way to correct that.

 

[xxxmonoxidechil]

This is to be expected anytime you weld a manifold pretty much. Heat warps metal.

The proper way to do this job, and not warp the manifold is to take a chunk of steel plate. Drill holes into it and basically mount your manifold to it. Then weld. Ive done this myself this way, and ended up with a perfect manifold luckily. Ive also done it the wrong way, and paid a metal shop damn near $100 bux just to shave my flange down flat again.

 

[Schwamm]

I took it back to the machine shop and they are planing it down and removing a few stuck and broken studs for $70. I feel a little ripped off since it seems this wouldn't have happened if they'd welded it correctly in the first place, but at least it's fixable