Leak proof valve cover gaskets

Having trouble with cork on stock cover. What do you guys use?

Have you tried Mr Gasket ultraseals?
Check with Superformance to see if they make a gasket suitable for stock covers.

Superformance Carbon-X Gasket. Best I've used. It sealed mine up; they're dry as a bone.

40 year old stock valve covers can be damaged in so many ways you might never get them to seal. I don't know any surefire gaskets for stock valve covers. If you have a good cast cover with a nice flat machined surface then there are several different gaskets that will seal up nicely.

What Andy says. Never had a problem with good cork gaskets, but I always spend time on stamped covers getting the rails dead straight & un-puckering the bolt holes. Cast covers are easier in that regard. The high-perf '68- '70 BB exhaust manifolds can bake calve cover gaskets, though, and the remedy I use for that is to replace them every few years before they start leaking.

I love my stock 340 valve covers but I have been fighting leaks for many years. I have used several different types of gaskets and sealants. I have also done the normal crack repair and straightening but those attempts did not stop all of the leaks. So I decided to add an aluminum spacer under the valve covers and two sets of the blue streak cork gaskets torqued to the stock 55in/lbs. So far the flat surface of the spacers seems to have helped the leaks even with cork gaskets.

I use spreaders on stamped valve covers to help keep the seal.

Get some cast valve covers. If you must have the originals on iron heads, the best way is to smooth the rail on the head and glue the gasket to the cover using (sparingly) The Right Stuff. The cast rail on original heads is terrible. Narrow and filled with porosity. You have a 3/8 flange on the valve cover that tightens down to a 1/8"-3/16" rail. Over tightening can be a bad issue. The factory had those little boomerang and other pieces over the top of the valve cover rail for a reason.

This is a restored, matching numbers, 440 4 speed Challenger. Can’t put cast covers on it.

The best I ever used for stock covers was the Felpro performance gaskets. Black rubberized. They seemed to work best on the stock cast head surface, but in time, they will still leak.

Well now you have oil leaks just like the original cars did. That makes it a correct matching number car. It probably also leaks from the transmission and the differential just like the factory cars did.

I switched to cast valve covers years ago, use a crush proof gasket like Superformance. Never any leaks at all.

You are officially the biggest ass hat on Moparts...........

Me, too...

Using the old 'high-temp' VC gaskets...


Bone dry for a LONG time...

Unless I had a need for OEM correctness, I'd never go back to stamped...

Blue Moroso Perm-align gaskets. Rubber with steel inner skeleton. Best I've ever used, no leaks, reuseable. I'll never run anything else.

I think the HP manifolds will burn them up no matter what you use. Are you running stock style exhaust on that Challenger?

this or SCE but I'm not sure if they make em for factory style VCs I have them on my B1s and they are leak proof.

I have the Realgasket brand on stock Hemi covers. They are molded from the red silicone with a fiberglass core. They seem to be doing the trick, if the directions are followed.

I have the black sheet metal covers from Hughes. Gonna have the flanges machined flat as they are not straight and use the carbon x gaskets this year.

One thing that caught me was I was using an old set of M/T covers on Indy heads, the underside of the cover where a bolt passes though was a different angle !! You think it tight but it isn't.

I glued/siliconed on rubber gaskets to 340 valve covers and used to pull the covers off a lot to run the valves. Never had problems or leaks. To me, cork is a leak waiting to happen. They heat set and once they do any further tightening just makes them crack or split. And scraping baked on cork from a valve cover is a pain. I'd rather peel off one rubber valve cover gasket.

YES , silicone the rubbers to the covers, let them dry and put them on and take them off for years.

Have never had a leak w/superperformance or moroso blue. I have had the moroso blues on my wagon for 5 yrs. In that time the gaskets have been removed w/the VC several times for routine lash checks.

Who are we referring too as the ass hat?

We only have the one leak on this car, the back of the valve covers.
Thanks for the ideas guys. I’ll order one of the suggested gaskets and see how it works.

X2

I don't think Dom meant that towards you.

Not you bro Mr Andy F...........

Thought so.

I purchased a set of Cometic valve cover gaskets due to a recommendation from Andy F a few years back. They are still working great. Also nice to not use any RTV or sealant on the valve covers or gaskets. I would definitely recommend everyone giving these a try.

https://www.summitracing.com/parts/cgt-c5983/overview/

https://board.moparts.org/ubbthreads/ubbt...gasgacinch.html

I ordered a set from Mancini racing of the super performance carbon x the other day so we will see. This motor came with a set of cast covers on it that were removed for the stock restoration. They had a gasket on them that was obviously not made to be removed OR reused. I had to pry them off. One corner of the cover was broken off by the previous builder because he tried to pry them off. Lol. They were stuck. They were grey and thick. I’ve never seen them before.

I like these from Fel-Pro. My intake doesn't sit flush with the valve cover rail and these are thick enough to deal with that interference. I have even had good luck using them over and over after valve lash checking etc.

https://www.summitracing.com/parts/fel-1...ASABEgKGbPD_BwE


I would imagine they make a similar one for a big block as well.

All -- there is no gasket better than its installation! Regardless of material:

1. Make certain mating surfaces are straight and flat; stamped steel tends to become distorted, so, re-flatten or replace. Cast aluminum tends to remain flatter and is preferred when that option exits.

2. Check the cyl head gasket surface -- some casting flash may exist and needs to be smoothed flat.

3. Clean the threadings -- eliminate friction of dirt (nuts, bolts, studs, etc).

4. Follow proper torque specs -- do NOT over-tighten!

5. Do NOT use RTV silicone on the gaskets as it only acts as a lubricant to allow the gasket top slip out of position! IF nthe gasket has installation tabs that can fit into the cover, that is what holds and positions the gasket to the cover. If no tabs, a quick-drying contact cement can be used (NOT RTV).

6. The gasket does the sealing, not any chemical.

There are hi-temp options of material to resist the extreme heat of the hi-rise exhaust manifolds... see the Fel-Pro catalog.

I worked as an aftermarket engineer with Fel-Pro for nearly 30 years and I know all the stories and issues. Read the directions -- I wrote them.

Love item 6.... and it is so true, make things flat, make bolt threads deep enough and things go well. I will only add that before you beat the sheet out of your bigblock valvecover flanges that you lay a flat bar on the head between rear and front cover bolt and the top ones, you will find it is not flat and straight. Make the cover fit the head, may not need to be straight.

Thanks for choosing Superformance Products fastmark.
I'm quite certain you will be satisfied with the performance and durability of these gaskets. Like all the others we manufacture quality materials for the job is at the top on our priority list.

Getting your previously used stamped steel valve covers straight is imperative to sealing just like any other gasket surface.

Read the included instructions and do not tighten down from the "center-out" technique. Instead, tighten from the lower rear working your way across the bottom row then on to the top in steps.

These have been out for 5(?) years now. Surprised everyone don't know about them yet, one of our fastest moving gaskets because they flat out work for people. Also listed here on moparts in the "New Products" page.