Modifying Mopar Performance Valve Covers

[MrFollmer]

A few months ago, I upgrade my ‘66 273 intake manifold and carb to an Edelbrock 4bbl set-up. In the process, I decided to change the valve covers to the aluminum black Mopar Performance ones. I installed it all correctly and noticed that the lip on the valve cover was making contact with the intake enough to prevent proper seal. So I did some searching online and realized that a simple modification would solve the problem. I marked the location of each contact point and went to town carefully grinding the lip down flat. I hope it works!

 

[pishta]

Yup, thats it! We all have done that mod once......You can stack 2 cork gaskets too if you dont want to grind them but then your stock bolts catch by about 2 threads.

 

[rumblefish360]

Thick valve cover gaskets have normally been hard to find. At summit racing, there search engine can help you find thicker gaskets for the futures

But otherwise, what your doing is nearly standard practice.

 

[Dartsun]

Great mod coulda used it. I remember when I first got into mopars I bought a black set of MP valve covers for my 273 They leaked on my 65 Dart,so I gave them to my buddy. Cool thing is he still has them 15+ years later.

 

[GEO]

Now you have gone and voided the life time warranty

 

[69_340_GTS]

Edelbrock valve covers need the same modification. Since they almost always hit on the manifold, I'd like to know why, after decades, the molds/patterns for these things never got modified?

 

[MrFollmer]

Now you have gone and voided the life time warranty

Haha....my lifetime warranty was all of about 2 months. A lifetime for non-functioning valve covers. I suspect mine will last well beyond my death!

 

[MrFollmer]

Edelbrock valve covers need the same modification. Since they almost always hit on the manifold, I'd like to know why, after decades, the molds/patterns for these things never got modified?

The original manifold sat just below the face of the head. So I can only assume that Mopar molded their version from the original versions that had a 1/4 inch of room there. Perhaps Edelbrock could mill a groove or shave a bit off of their aftermarket manifold. But you're right...Mopar should make a small line on the inside of the cover to show where the metal could be removed if it's hitting. Regardless, I enjoyed the process of modifying it - kept me in the garage with a beer and outta the wife's hair for a few hours.

 

[69_340_GTS]

I really think that if you buy an Edelbrock intake, heads, and valve covers, they should all fit together without modification. They even sell the parts together as some kind of "kit"! But ...Surr-prise! They don't really get along with one another.

 

[gzig5]

I really think that if you buy an Edelbrock intake, heads, and valve covers, they should all fit together without modification. They even sell the parts together as some kind of "kit"! But ...Surr-prise! They don't really get along with one another.

Because making them work together would require effort. Effort=cost. Either their profit goes down or the product price goes up. Then you have all of us who are willing to put up with it and modify the parts so they do work together, which is another incentive for them not to invest in change.

 

[69_340_GTS]

Because making them work together would require effort. Effort=cost. Either their profit goes down or the product price goes up. Then you have all of us who are willing to put up with it and modify the parts so they do work together, which is another incentive for them not to invest in change.

But I'm quite sure that valve cover rail is all machined. Sure appears to be. Probably on a CNC machine. (At most) it would take 5 seconds longer to machine the extra material off. Hell, if they sent me their CNC program I'd even edit it for them for free!

 

[gzig5]

But I'm quite sure that valve cover rail is all machined. Sure appears to be. Probably on a CNC machine. (At most) it would take 5 seconds longer to machine the extra material off. Hell, if they sent me their CNC program I'd even edit it for them for free!

My M/T and Mopar Performance are as cast. There were no machining marks on the rail.

I hear you, but I work in product development for a large company and if there is any way to remove steps and processes, they will do it. In the long term with volume, it means millions of dollars each year to the bottom line. The other side of the coin is if you did provide that relief cut, it wouldn't be perfect for every application and half of the guys are going to ***** they could do it better. Lose-lose proposition unless you are doing it for a specific head and intake combo on a specific motor. Then you have some control over the variables, or can at least account for them. Most larger companies like Edelbrock or what was Mopar Performance are not driven by the small customers. They listen to the big customers that bring in big orders. Small companies can be more responsive, if they choose to.