Wrong exhaust manifold? or warped?

[Jake_Goldstein]

I'm converting an 82 na engine to a turbo, and my new used turbo exhaust manifold doesn't fit quite right on the studs into the head. I can't get the rear-most stud on cylinders #1 and #2. i don't think it's a face flatness issue: i just can't get the holes to line up right. A few questions:

 

1) Could I have the wrong manifold? could I have accidentally gotten a different year, and the holes just don't line up? The new used turbo exhaust manifold I have does not have an EGR port on it, and the old NA manifold did have an EGR port. is that a clue? I got this manifold from a guy in Austin parting out a lot of cars, so it's possible we got mixed up? I can get all the studs in except the #2 screw (back one on the 1st cylinder) and the #4 stud (back one on the 2nd cylinder).

2) If all the manifolds are the same, then is there something I can do, like drill out the stud hole on the manifold a little bit? Is there some wiggling or prying trick I can try to get them to line up? The two holes are off by about 1/8" or so.

3) The face of the manifold is still flat. Could I have warped the manifold welding on the turbo wastegate flange, and still have the manifold face flat? I had a professional welder do the welding, I'm not that good.

 

Thanks to all the posters here, I've learned a lot from you all.

 

Jake

[kelltainer]

you may want to post them up on the s130 series section and try some search options for it.

[Ineptitude01]

This happened to me also. The head and exhaust manifold go through many many many heating and cooling cycles for a number of years, and after a long time, they have the same slight variances. Different engines will heat and cool differently, and from that, they'll have different variances.

 

I had a broken stud on the turbo manifold that came with the engine, so I used one from an 81 L28ET with a thrown rod. The 81 manifold was ever so slightly different than the original one had been, so I had the same problem. It just took one long night of wiggling and dead blow hammering to get it to go on right. And after all was said and done, it wouldn't fit with the intake manifold, because it was just slightly different in shape.

 

I had to take it all back off, and use a dremel on the edges of it (NOT THE SEALING SURFACE) to get it to hook up right.

 

Hope this helps.

[Jake_Goldstein]

Thanks, I think I'm going to do the same: just use a Dremel to hog out the hole in the manifold a little bit. Looks like I might have to take 1/16" off, and it's 1/4" thick or more near the holes, so here's hoping it works. I appreciate the response.

[jasper]

Reminds me of this tool for chevy manifolds, that had dimensional issues.

 

http://www.amazon.com/Lisle-13000-Manifold-Spreader-Chevrolet/dp/B0009OR94W

 

Never owned, or had to use one. But I'm thinking a common problem..........

[Jake_Goldstein]

Well, the Dremel worked like a champ, and the manifold fits fine. My lesson: a small amount of grinding on the stud holes of the manifold is probably OK. Thanks to everyone here.