Here's what finally worked for me to get a tight, leak free seal:
1) Buy 2 sets of Fel-Pro 4 bolt cork gaskets. (Rockauto.com is cheapest I've found) You can also buy the 6 bolt gaskets and trim off the 2 holes not used.
2) Using black RTV silicone SPARINGLY, glue 2 gaskets together, so that you've doubled the thickness.Place a flat board on top of these and let them sit for a few hours.
3) Using black RTV silicone SPARINGLY, glue the doubled up gasket to the surgically clean valve covers.
4) Wipe down the sealing lips of the heads with acetone until there is absolutely NO oil on them.
5) Using black RTV silicone, apply a THIN bead to the lip of the heads. I then use a finger to smooth this bead flat. A minimum thickness works best and is easiest to remove down the road.
6) You'll need bolts or studs that are approximately 3/16" to 1/4" longer than stock. If using bolts, maske sure they won't bottom out in the holes.
7) Set the covers on the heads and try not to move them around. Using a nut driver, gently tighten the fasteners down until the bolts or nuts contact the covers. THEN STOP!!!
8) Wait a few hours and then tighten them again with the nut driver or a 1/4" ratchet, holding the ratchet near the ratchet head so that you can't apply much torque. You want the fasteners only hand tight.
9) Let it sit overnight without starting it. After you run it up to operating temperature for the first time, let it cool and take it a little tighter, maybe 1/2 a turn. If you experience any leaks, gently take another 1/2 turn.
Using this procedure is a hassle, but since doing it this way I've not had any leaks. I'm sure others have had success with different procedures, but I was asked, and decided to share.
Fel-Pro 4 bolt #VS11703C $10.67 a pair at Rock Auto
Fel-Pro 6 bolt #VS13379 $5.53 a pair at Rock Auto (on closeout)
1) Buy 2 sets of Fel-Pro 4 bolt cork gaskets. (Rockauto.com is cheapest I've found) You can also buy the 6 bolt gaskets and trim off the 2 holes not used.
2) Using black RTV silicone SPARINGLY, glue 2 gaskets together, so that you've doubled the thickness.Place a flat board on top of these and let them sit for a few hours.
3) Using black RTV silicone SPARINGLY, glue the doubled up gasket to the surgically clean valve covers.
4) Wipe down the sealing lips of the heads with acetone until there is absolutely NO oil on them.
5) Using black RTV silicone, apply a THIN bead to the lip of the heads. I then use a finger to smooth this bead flat. A minimum thickness works best and is easiest to remove down the road.
6) You'll need bolts or studs that are approximately 3/16" to 1/4" longer than stock. If using bolts, maske sure they won't bottom out in the holes.
7) Set the covers on the heads and try not to move them around. Using a nut driver, gently tighten the fasteners down until the bolts or nuts contact the covers. THEN STOP!!!
8) Wait a few hours and then tighten them again with the nut driver or a 1/4" ratchet, holding the ratchet near the ratchet head so that you can't apply much torque. You want the fasteners only hand tight.
9) Let it sit overnight without starting it. After you run it up to operating temperature for the first time, let it cool and take it a little tighter, maybe 1/2 a turn. If you experience any leaks, gently take another 1/2 turn.
Using this procedure is a hassle, but since doing it this way I've not had any leaks. I'm sure others have had success with different procedures, but I was asked, and decided to share.
Fel-Pro 4 bolt #VS11703C $10.67 a pair at Rock Auto
Fel-Pro 6 bolt #VS13379 $5.53 a pair at Rock Auto (on closeout)
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