I have been wrestling the passenger side header (hedman elites...3/8" flange) on alum heads for a few days. I have changed the gasket 4 times and tightened the bolts several times (from center to end) and it seems like the entire top of the passenger side header just don't want to seal. First started with paper/cardboard gasket and they burned right through...then put on mr. gasket ultraseals (composite) and burned through 2 of them (one is on the driver's side and it seems fine). Being desprate I spent the $ on the recommended aluminum Percy seal-4-good dead soft aluminum ones and I can't get them to seal !!! This is getting rather annoying and expensive. Been recommended to try stock exhaust gaskets or the cardboard type but first soak in water overnight. These headers have less than 1000 miles on them and previously before removal it was sealed fine. I am guessing the flanges are warped or there is something up with the welded ends and them sealing...either way I was sure they woud seal up with the Percys. Any suggestions ? I am ready to tear these things off and replace them with exhaust manifolts.