What header gaskets are best? '05 5.4. I put JBA headers couple years ago, and i think passenger side may be starting to leak again. Is it possible my head is not true and flat anymore? Before changing mainfolds due to leak, i did drive it a lot and hard. Maybe 15k with leak

 

It's most probably the header flange that's not flat. The mounting surface of the head is probably flat enough. You can lay a staight edge along the mounting surface of the head and the header flange to check. Mr. Gasket and Fel Pro both are good quality gaskets.

 

thanx, im putting new quick lift struts this wknd and thought since im that close whats a gasket and another hour or 2

 

When I use to install headers on my engines I would use Mr. Gasket copper gaskets with Stage8 header bolts.The copper forms to the irregular spots of the header flange.The Stage8 bolts have a snap ring and retainer that goes on the bolt head and locks against the header to keep the bolt from backing out.

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