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buckskins4ever · 04-03-2013, 02:15 AM

Its not the age of the holes that is causing header bolts to back out. Its one to two reasons they back out. One is Headers are not perfectly flat. The other is the gasket. Depending on which gasket you go with you end up with wither a faulty paper thin one that blows out, or you go with one designed to heat up and seat and seal the gaps between header and head exhaust ports.
Aluminum and Copper are designed to be a crush style gasket and unfortunately both of those metals heat up and form as supposed to but as they do so the create loose bolts. And since they dont expand once cooled, they dont tighten bolts back up that are now loose...thus causing the effect that they are backing out. Problem is you dont catch it and they actually do start backing out now that they are loose anyways.

RimFlex on the other hand are a composite type material like CarbonFiber with Metal inlaid in to it. this gives the added structure and its not expanding or crush style material. CarbonFiber holds a very high heat threshold and is as strong as steel. No blowouts, no warping, no crushing, no leaks. It took me more than $200 wasted dollars and hours of re-tightening bolts.

04-03-2013, 02:15 AM	#16
buckskins4ever Registered User Join Date: Dec 2012 Location: Altoona Iowa Posts: 481	Re: Header advice Its not the age of the holes that is causing header bolts to back out. Its one to two reasons they back out. One is Headers are not perfectly flat. The other is the gasket. Depending on which gasket you go with you end up with wither a faulty paper thin one that blows out, or you go with one designed to heat up and seat and seal the gaps between header and head exhaust ports. Aluminum and Copper are designed to be a crush style gasket and unfortunately both of those metals heat up and form as supposed to but as they do so the create loose bolts. And since they dont expand once cooled, they dont tighten bolts back up that are now loose...thus causing the effect that they are backing out. Problem is you dont catch it and they actually do start backing out now that they are loose anyways. RimFlex on the other hand are a composite type material like CarbonFiber with Metal inlaid in to it. this gives the added structure and its not expanding or crush style material. CarbonFiber holds a very high heat threshold and is as strong as steel. No blowouts, no warping, no crushing, no leaks. It took me more than $200 wasted dollars and hours of re-tightening bolts.