coppercutlass

Today i bought some valve cover gaskets to wrap up my roller rocker install. I have been having issues with valve covers sealing properly. So i bought new valve covers and new gaskets. and they still leaked. i took it all back apart and analyzed it all . The fel pro gaskets will not work with some after market covers as the edges dont allow for the gasket to properly form and subsequently shove the rail seals inward when the cover is put on then some holes also dont line up making it worse . I was using a new set of moroso valve covers the old school tall ones. Now i grabbed my old chineeseum covers that are 3/8 taller than stock and the gasket lined up BUT there is also another issue with the gaskets when i put them on a set of spare sbo heads i have there is one bolt hole that does not line up at all AND its on the bottom rail the most important one !!!!. So be careful and dry fit you gaskets make sure all your bolts will go in with no resistance and that they will fit inside the cover its self. i fit it to the cover and to the heads to rule stuff out. i trimmed and elongated the bolt holes as the sealing surface was covered. I hope i get no more leaks as i got my gaskets to fit dry nice and even after the trimming ., but im letting any do it your self guys to be careful with the install as i think the quality of the gaskets is going down hill.

the part number i used was felrpo vs50259R

olds 307 and 403

I too had issues with those gaskets on chrome covers. I would try the Edelbrock or Ultraseal with steel cores.

coppercutlass

For now i used the china covers with the trimmed gasket. I trimmed the fat around the outside diamter to properly keep the inside areas good for proper seal. Im gonna try the ultra seals next when i use the moroso covers on the new engine.

redoldsman

Interesting about the Fel Pro gaskets. Back in the day (that would be the early to mid 60's) we all used Victor gaskets. Nobody wanted Fel Pro because they didn't fit worth a flip. I haven't seen Victor gaskets in years. I did a couple internet searches and they were bought by Dana Corporation in 1966 and are now known as Victor Reinz. Maybe they sell in Germany now. It is funny how some of the old trusted brands disappear.

coppercutlass

Carquest carried victor reinz and i liked them as well. for years i wondered why i could never get the valve covers to seal properly now i know why. i thought i was doing something wrong but it was not me . The only valve cover gaskets that i have had seal right are the old cork ones.

What i did to make sure my gaskets laid right is i grabbed my valve cover studs and put them on a spare set of cylinder heads and laid a thin bead of silicone on the side that seals against the valve cover ( after trimming and installing on the spare head) then i bearly snugged them. that way when i install them the gasket does not move and it seals properly.

Destructor

The rubber gaskets on my chrome valve covers initially leaked but every few day I would gently hand torque the bolts, sometimes only a quarter turn. If much effort was required I'd leave that particular bolt alone. After a couple weeks the leaks stopped. There is very little sealing surface around the bolt holes.