Well…should have listened to 5wndwcpe…after trying standard exhaust gaskets and header gaskets…decided to get high temp permatex gold. Third time was the charm. Sounds great now. I just hope it lasts. All depends what the situation is I guess. The shop that did my heads did not face the exhaust port surfaces. I was surprised…and my exhaust manifolds had pitting so I had no choice. In my case, gaskets obviously didn’t work but Permatex gold did. I just hope it lasts.