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Old 10-10-2012 | 03:16 PM
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Default CMI header mounting hardware

Just wondering what your all using to keep your CMI's mounted up nice and tight. Just stainless bolts? Locking header bolts? Thread locker?
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Old 10-11-2012 | 01:33 AM
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My CMI headers on my AT are just bolted with the standard header bolts. They do rust some, but have stayed tight for the 5+ years I've owned it.
On My Pantera, I used the ARP stainless header studs and nuts. They looked much better and stayed tight as well.
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Old 10-11-2012 | 03:42 AM
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I have a combination of studs and bolts. No problems.
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Old 10-11-2012 | 07:12 AM
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I use 1 1/2" 3/8x16 stainless socket head cap screws. Buy them at the fastener shop up the street from me.
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Old 10-11-2012 | 12:07 PM
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Probably one of the most important things to do to keep them tight is to retorque the bolts/nuts after the first time they have been run for a few hours.
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Old 10-11-2012 | 12:46 PM
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so whats the torque spec ft # , or does it differ on the type of header or bolt, I think Im gonna use the ARP stud and 12 point nut on mine.
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Old 10-11-2012 | 01:19 PM
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Problem with studs and nuts is getting them on and off in tight engine bays. With the socket head cap screws (Allen) bolts a ball end Allen socket can get on every bolt and with my e-tops I had on my hawk I could get at every bolt with a dewalt cordless impact.
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Old 10-11-2012 | 06:40 PM
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Originally Posted by lil red
Problem with studs and nuts is getting them on and off in tight engine bays. With the socket head cap screws (Allen) bolts a ball end Allen socket can get on every bolt and with my e-tops I had on my hawk I could get at every bolt with a dewalt cordless impact.
Sounds like a good idea. Probably a bit cheaper than ARP too....

Last edited by Baja226sport; 10-11-2012 at 06:40 PM. Reason: spelling
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Old 10-12-2012 | 01:51 AM
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Originally Posted by 33outlawsst
so whats the torque spec ft # , or does it differ on the type of header or bolt, I think Im gonna use the ARP stud and 12 point nut on mine.
I used the 6 point nuts and did not have any issues. With the 6 points, you have some greater flexability to get a wrench on them from the side instead of having to get an entire closed end wrench over and around the nuts.

I think spec is 30 or 35 #'s, but I never actually used a torque wrench. There just is not room on most of them. Just snug them up tight with using a normal length 3/8 ratchet or wrench.
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Old 10-12-2012 | 06:33 AM
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allen head's a good idea, I just thought it would be easier with studs cuz you could hang the gasket on the studs and place the header on, and tighten, Im a new-bi to headers on a boat, installing some on my rebuilds this winter.

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