I have struggled sealing 2 areas on my Hemis. The first was the intake. Superformance gaskets with high tack has finally dealt with that.

The second area is the valve covers. I have original stamped steel covers on MP/Edelbrock heads. After trying several different things, I have finally found some really cool gaskets. Fel-Pro #1629.

I had already tried the regular Fel-Pros, not knowing that they also made these "performance" gaskets.

Each of these #1629 gaskets is 2 cork/rubber gaskets with a steel mesh laminated between them. They are over 1/4" thick. If these don't do the job, I don't know what will.

One down side to these gaskets, though. The holes in the gaskets did not line up well with the studs. I had to use a Dremel tool to slot most of the holes so that they lined up. The gaskets are plenty wide, so there is more than enough material to make this adjustment.

Amazon has the best price on these, by far.

FYI