G_Body_Man HalfDork
6/20/15 11:28 a.m.

So the Cutlass needs new valve cover gaskets for sure, so I figure that it's better to do them now than later. My question is: what type of gaskets should I go for? I want the OEM thickness because clearance is an issue, so I'm just wondering should I buy the cork set or the rubber set? Thanks.

edizzle89 HalfDork
6/20/15 12:36 p.m.

if you dont want to buy new gaskets every time you remove the valve covers rubber is definitely worth it.

Knurled UltimaDork
6/20/15 12:53 p.m.

Unless you have sheetmetal valve covers in which case the conformability of cork is worth it. They can be reuseable if they come off in one piece, too, if they aren't too old and you really have to.

Granted, Olds engines seem to always drool from the valve covers. I've always had the best luck with cork. One time I even got a 307 to stay dry!

G_Body_Man HalfDork
6/20/15 1:37 p.m.

It's got an LG4 in it, if that helps.

81cpcamaro Dork
6/20/15 1:47 p.m.

I prefer the rubber gaskets over the cork ones, but the cork can work too. Make sure the cover flange is straight as you can get it. Then glue the gaskets to the covers, I usually use Permatex #2 gasket sealant, only on the valve cover side.

Streetwiseguy PowerDork
6/20/15 1:53 p.m.

Perimeter bolts, or center bolts? I presume perimeter, I don't think you can buy a cork center bolt.

I like cork. Advantage to cork, you can glue them to the valve cover with contact cement, and they will stay there forever. Rubber, I've never found a glue that does much other than making them slip out of place. You need to flatten the flanges around the bolts. They will be sucked down, most likely. If you can find a set of "Corvair holddowns",

they help a bit. Don't overtighten cork the first day, but snug them down about as firmly as you can with a 1/4" drive ratchet, then tighten them weekly until they stop compressing.

Theres 30 years worth of small block Chevs out there with the valve cover rail too damn close to the exhaust ports. They all harden up and drool.

G_Body_Man HalfDork
6/20/15 4:30 p.m.

In reply to Streetwiseguy:

Perimeter bolt, one side of each valve cover is quite close to the header. Who knows, I may even repaint my valve covers and air cleaner with hi-temp wrinkle paint.

patgizz PowerDork
6/20/15 4:31 p.m.

rtv cork ones to the valve covers, then they come off in one piece every time with the cover and are reusable.

G_Body_Man HalfDork
6/20/15 4:44 p.m.

Should I go for 5/32 cork or 7/32 cork?

Knurled UltimaDork
6/20/15 4:54 p.m.

Thicker is definitely better. The valve cover WILL warp a little when you snug the bolts, this is just a fact of life. Thicker gaskets moosh more and absorb the warp. They'll settle with heat more as a side consequence, so as noted upthread you'll have to keep up on them by gently snugging the bolts every so often.

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