There is a company called remflex that makes a very thick header gasket i see them at the local carquest when i go in there, i should mention that my local carquest is a special one that deals with race parts as well as replacement auto parts so they deal with some very neat stuff. Well anyway back to my point the sprint car racers around here swear by them but again they are very thick at least as thick as five header gaskets put together each and they look to be made out of a similar material as newer cars head gaskets those that are made to make up for slight variations in the deck of the block and head. Anyway i havent used any yet but again the sprint car guys love them and as they are spending 50k plus just on their engines i would think they are only about quality. I plan on trying a set on my car when i install headers my only worry is they will be to thick and put the header to far out there but i wont know till i try. May want to try them if you cant get it to stop leaking. Good Luck Justin