Sealing up valve covers
First off, make SURE the valve cover is able to tighten down properly, and isn't interfering with the intake manifold... many aftermarket manifolds have taller runners and meatier flanges that contact the lip of the valve cover, preventing it from tightening down fully. Yes, even the stock stamped covers can have this issue. Usually a little judicious grinding in selected areas of the valve cover lip solves the problem.
Also, are you using the little triangular valve cover washers? They're pretty much a necessity on the stamped v.c.s- they help to distribute the load without as much distortion. Even the factory was using them after time went on...
https://www.jegs.com/i/Mopar-Perfor...m_term=4581596255650123&utm_content=Evergreen
First off, make SURE the valve cover is able to tighten down properly, and isn't interfering with the intake manifold... many aftermarket manifolds have taller runners and meatier flanges that contact the lip of the valve cover, preventing it from tightening down fully. Yes, even the stock stamped covers can have this issue. Usually a little judicious grinding in selected areas of the valve cover lip solves the problem.
Also, are you using the little triangular valve cover washers? They're pretty much a necessity on the stamped v.c.s- they help to distribute the load without as much distortion. Even the factory was using them after time went on...
https://www.jegs.com/i/Mopar-Perfor...m_term=4581596255650123&utm_content=Evergreen