What are better valve cover gaskets for a car? Cork kind? Or the rubber kind? Or either rubber/cork kind?
cork gives u a better seal
that depends on what shape your valve covers are in. if the sealing flange is good and straight and not bent. then I would use cork as long as you don't over torque the bolts. But if you have a flange that is bent or wrinkled use the rubber ones, they will conform to the shape of the cover and you can tighten them a bit more. if you have a serious leak use the rubber kind. want a little racer trick. take a coke can and cut eight strips out of it that are half as wide as your gasket. place them at the corners of each cover don't go into the corner just up to it. this will help seal the corners better. but I still prefer cork to rubber.
For the inexperienced I would choose rubber it is harder to mess up by overtightening and if you clean the surface it will seal good
