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Header flanges shrunk

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Old May 1, 2008 | 07:05 PM
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Angry Header flanges shrunk

My car has been down for about 6 months. I few weeks ago I put on some new heads. Came time to bolt up the headers and the bolt holes did not like up. I thought the problem was with the new head so I removed the headers and tried to bolt it up to the old head. The bolt holes do no line up. They are off by about 1.5mm. I can get in the 2 middle bolts and the 2 to either side, but not all 6 at the same time. I had no problems when they were removed a couple months ago. They are kooks 1 7/8. Any ideas what could have caused this?
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Old May 1, 2008 | 07:27 PM
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I had a similar problem. I just had to barely start the bolts and then tighten them from there.
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Old May 1, 2008 | 08:54 PM
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^ there should be a little wiggle room in each bolt hole on the flange. I had this happen before and I was about to throw a header through the windshield. I had to just start each one a little and make it line up before tightening them down.
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Old May 1, 2008 | 09:27 PM
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They are not tightened down. They are in just a couple threads. It is not a problem of improper installation.
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Old May 1, 2008 | 11:02 PM
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I would take a dremel and widen the holes in the header. You don't want to stress the bolts going into your aluminum head. I turned all my header bolts in by hand almost all the way before putting a wrench on them. Make sure you put some anti-sieze on those bolts and never force them.
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Old May 2, 2008 | 12:03 PM
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Originally Posted by massls1guy
I would take a dremel and widen the holes in the header. You don't want to stress the bolts going into your aluminum head. I turned all my header bolts in by hand almost all the way before putting a wrench on them. Make sure you put some anti-sieze on those bolts and never force them.
Good post. Id suggest the same.
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Old May 2, 2008 | 12:15 PM
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+1 Dremel time. Take a little bit off each hole, not a lot out of one, btw.
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Old May 2, 2008 | 02:05 PM
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Anti - seize on header bolts ???? I did that ONCE . After losing header bolts going down the road and then I had to forever tighten them at least once a month . screw that ! LOL !!!

To each his own , but aint no way im doin that . I can see putting anti-sieze on your spark plugs though . BTW, I have never had one problem with stripping bolt holes or header bolt loosening or losing bolts. They always come right out without anti-seize . Maybe im just lucky IDK .
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Old May 2, 2008 | 03:13 PM
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We've drilled out header flanges before too. I put either anti seize or thread locker on every bolt I turn. Went with the locking "Stage 8" header bolts and haven't had any problems.
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Old May 2, 2008 | 03:30 PM
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I agree with the thread locker . . . IDK maybe I used too much anti-sieze , but I will never use it again because of my bad experience . As always YMMV . . . .
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