James J

The instructions for the Fel-Pro Valley pan gasket says to use silicone around the ports. The Edelbrock performer says to use gasgacinch & not use the rubber end seals; but a bead of silicone. I'm inclined to do the Fel-Pro way 'cause I think the rubber end & silicone on ports would be stronger. What do you guys do? Thanks Jackson

Olds64

Make sure you use the Right Stuff gasket maker in place of the end rails.

https://classicoldsmobile.com/forums...ations-167288/

VC455

Rubber end-rail seals shrink and harden with time, the leaks continue to get worse.

I've not had a leak since I began to use silicone in place of the rubber rail seals.

The correct place for the rubber end-rail seals is in the trash can.

oldcutlass

You want to follow the instructions for the valley pan steel gasket and use RTV on the ports. The Edelbrock recommendation is for the use the Gasgacinch on a fiber gasket. The main reason not to use the end rubber seals is because they may not allow the manifold to seat fully on the port gaskets and cause leaks in the ports, cause the end seals to squish out, or potentially crack the manifold. The RTV in place of the rubber end seals allows for a perfect seal.

BillK

I use Permatex Aviation Form a Gasket on the intake ports and just a little bit of Right Stuff on the water ports. Like everyone else said just a bead of Right Stuff (or any good RTV) on the ends. You definitely do not want to use the rubber end seals.

joe_padavano

Permatex ultra black around the water ports and as a replacement for the crappy rubber end seals. Been doing it that way for years with zero issues. Also, be sure to dry fit the gasket FIRST and ensure that the locating bosses fit correctly into the holes in the heads. I suspect that failure to do this (as well as general failure to read and follow directions) is why so many people have problems with the stock gasket.

olds 307 and 403

I use Permatex Aviation sealant around all the ports except the end, the Right Stuff or Optimum Grey if you like the high torque stuff on the 4 water ports. I go on both sides of the gasket. I chuck the rubber end seals. Also build up the end beads tall and narrow. I do 3 beads, tall, had it leak not doing tall enough beads.