460 header question
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460 header question
I have new headers on my 96 F350 4x4, so I know the flanges aren't warped, but still keep blowing out header gaskets. The engine is low mileage and never had a leak with the manifolds on. The exhaust tick is very loud and I think that because the exhaust is escaping before the o2 sensor that the truck is getting worse mileage than it should. Does that sound right? I tried using felpro's but those suck too. Does anyone know were I can find a really good sealing exhaust header gasket? Maybe something copper or with an O-ring?
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In many cases the exhaust hangers do not support the exhaust the way they should and the headers are acting as the support. During a heat cycle, there is tension placed on the header bolts and the added weight compunds sealing issues.
If the bolts are coming loose, the gaskets will blow out quickly. Make sure that you tighten them properly and make sure that they stay tight. You may have to tighten them every few heat cycles until they can maintain enough tension to stay tight.
Improper fuel mixture conditions or even poor exhaust flow can create added heat in the header and cause the header to expand to the point that it will loosten the bolts and this condition will tear up some gaskets.
Few different possibilites, but there is an answer.
If the bolts are coming loose, the gaskets will blow out quickly. Make sure that you tighten them properly and make sure that they stay tight. You may have to tighten them every few heat cycles until they can maintain enough tension to stay tight.
Improper fuel mixture conditions or even poor exhaust flow can create added heat in the header and cause the header to expand to the point that it will loosten the bolts and this condition will tear up some gaskets.
Few different possibilites, but there is an answer.
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there tight alright
After the first replacement exhaust manifold gaskets I blew out, I installed Stage 8 Locking Fasteners. The exhaust system I installed is suspended perfectly, creating no pressure on the header-to-head bolts also. Still I blow out gaskets. There has to be a really good Exhaust manifold gasket on the market that will seal a 1996 460 and not blow out after 3 runs.
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ok, next step is to take off the headers and smooth out each port where there welded. be careful and dont go to low,inexpencieve ones will have all of their welding on the inside of the flange. if your not sure about what im talking about ,run a straight edge along the edge that fits the head.
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From: Nashville NC
In my old motorhome which has a 454, I switched to the copper type exhaust gaskets & had no more leaks. It had the old cast manifolds, but still were prone to leak or crack.
From what I've read, the thickness of the header flange that bolts to the head make a lot of difference. Thin flanges, you have more problems keeping them sealed up. The better headers have at least 3/8" thick flanges, so they retain their shape better.
Heard a few Ford guys say if the flange is one piece, they cut the flange in between each port unstead of it being all together. Dont know if thats better or not, just what I've heard.
Neil
From what I've read, the thickness of the header flange that bolts to the head make a lot of difference. Thin flanges, you have more problems keeping them sealed up. The better headers have at least 3/8" thick flanges, so they retain their shape better.
Heard a few Ford guys say if the flange is one piece, they cut the flange in between each port unstead of it being all together. Dont know if thats better or not, just what I've heard.
Neil
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I've got a set of Remflex gaskets waiting to install, heard mostly good stuff about them. Don't buy them from Remflex though, mine would have been $39 + shipping, I paid $29 shipped through Amazon. Just find your part # and do a google search.
http://www.remflex.com/
http://www.remflex.com/
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I've got a set of Remflex gaskets waiting to install, heard mostly good stuff about them. Don't buy them from Remflex though, mine would have been $39 + shipping, I paid $29 shipped through Amazon. Just find your part # and do a google search.
REMFLEX Exhaust Gaskets: Home Page
REMFLEX Exhaust Gaskets: Home Page
After over 6 months of use I am very impressed with Remflex gaskets. I retorqued 3 weeks after install and found them a bit loose, finally went to recheck them again last week and they were still perfectly tight. No leaks, even when they were kinda loose in the 3 weeks after I installed them. The truck is a daily driver that gets used as a tow rig about once a month, and the Hedman headers are not what I'd call top shelf quality. Best header gaskets I've ever used. Worth the $$$
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