Valve Cover Gaskets

I have a 440 with alum. heads with Black Mopar Perfomance valve covers on them and I have used three diffent sets off gaskets (cork twice, cork & rubber combo) and still have a leak on the outside rear corner on both sides has anyone had this problem or is there a gasket set anyone can recommend. Thanks  

This may or may not be the problem. I had a leak similar to yours. I found because I had milled the heads the valve covers were not seating properly, they were butting up against the intake manifold. The proper fix would have been to mill or grind the intake, but I wasn't up to taking the manifold off. So I installed two sets of gaskets on the valve covers. I glued one set on the night before with silicone, then I installed a second gasket and tied them onto the valve cover with copper wire strands from 14 gauge wire. Again using silicone in between the gaskets. This worked well and I have had the covers on and off a couple dozen times over the yrs. because I have an adjustable valve train.
Tom  

Try some Moroso "Perm-Align" steel-core rubber v/c gaskets, #93055. They are awesome.  

Ok so I have tried all of the above and still can not stop it from leaking. With RTV on them they will last two heat cycles then will start to leak again any other ideas?  

I'd have to guess that the v/c is hitting something before the gasket has a chance to compress.  I know on small blocks with Edelbrock heads, most v/c will hit on the top edge of the cast pedestals that hold the rocker arm shafts. Plus investigate what someone else said about hitting on the intake manifold. Check for interference. The v/c must be getting hung up on something.