Valve Cover Gasket

[Stinger]

My son has an '82 Eagle with the 258.  His engine still has the original factory valve cover that's indented on both sides for bolts.  He is having a very hard time finding the correct gasket for this valve cover.  Does anyone know who makes a gasket and what the part number is? 

[El Matador]

The first name that comes to mind is Fel-Pro.  I have a few different versions of 258 valve cover gaskets still in their boxes, so when or if time allows I'll check the numbers.

[Stinger]

I think I may know why he has had such a hard time finding a gasket.  It appears that the cylinder head and valve cover may have been changed on his car.  I think he has parts from an '80 or earlier 258.  The other issue making things difficult is he is looking for a rubber gasket.  He doesn't want cork.  I think he may be SOL.

[IowaEagle]

Sure does sound like he has an earlier head as '82 used the plastic valve cover.   Are you sure its not a 4.0 that got transplanted?? The '80 and earlier covers were steel.  I think the 4.0's may be aluminum???

[Stinger]

The valve cover does look like it may be steel.  It's definitely not aluminum.   

[IowaEagle]

I would check the build date on the block to see if it was an entire transplant or just a head transplant.  The '80 and earlier heads used 1/2" bolts, after that AMC went to 7/16".  They can be successfully interchanged and there is a head bolt bushing kit that can be used to make up the difference.

[carnuck]

Are you sure it's not plastic?

[captspillane]

The 1979 and older 258s use a steel valve cover with reportedly the same footprint as any other 258 or 4.0. They went to plastic then to aluminum in late 1987. The 1988 aluminum valve cover is slightly different, but has the same exact bolt pattern as a 1995 4.0. In the late 90's the valve cover went back to being steel.

Some people have installed aftermarket aluminum valve covers, designed to replace the plastic ones, on the earlier heads. The gaskets themselves are the same. The newer stock covers have also been modified to fit supposedly. The problem is that the plastic valve covers only have three bolts along the side while the newer ones have more than that and the older ones had metal spacers that clamped onto the metal lip and a different set of holes. As I understand it there is a place to drill and tap the later holes into the head or means of clamping the aluminum valve covers.

Here are some pictures of a 1978 258 that I found online. Its obviously steel. The two orange pictures are after a 4.0 head conversion, so thats the new aluminum cover from about 1992.

[mudkicker715]

technically 80 and older. not 79 and older. however someone made a steel replacment. i have atleast 1 in the basement. my 84 when i got it had a leaky chrome plated cover. so anything is possible.

[carnuck]

I have (or had) a couple of the 79-early 81 heads with the tin cover. They had an issue with #2 intake guide jamming on the valve and bending pushrods. They are in my stuff for sale pile (along with the covers) if they didn't go in the last disgusting pile of scrap metal I took in to make the payment on my cabin last summer when I was cut back to part time at work. (I even took in my Dana 70 from a CJ10A diesel tug)