Been using FelPros rubber cork gaskets until lately. I reused them a few
times, and just torqued down a little more on the valve cover bolts to prevent
leakage. When I went to put on the Moroso gaskets, there were bits of rubberized
cork laying near the bottom of the valve spings. Some slivers where almost 1/2 inch long. The gasket was breaking off near
the bolt holes, where the bolt torque was causing the most clamping force. So, don't go too
long with the same gasket, or you'll have ruberrized cork clogging your oil system!