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 http://members.tripod.com/mopar_roadster/overheating_cure.html

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The Cure ???
 

    First to answer all the hoopla and concerns I’ve read about ‘THE CURE’, over the last couple of weeks I’ve been doing my research. If I can physically prove a engineering change (and I think I will) that Mopar made in the quest to meet emissions that maybe causing all or some of our over heating problems, it would be of great benefit to all.

    I’m going to put some validity in ‘THE CURE’ and hopefully put it to bed. After doing some digging and research, opposed to the physical (as in just doing it). I’ve come up with some very interesting information, which I will reveal here and now. But will ask from some additional help from fellow MMLers to further validate this information.

    First off one clarification that needs to be make, ‘THE CURE’ DOES NOT' involve port matching, I talked with Ron and he NEVER said to match the water jacket ports.

    OK. Now with that said here we go.

    In my hands I hold three, count them three head gaskets for a big block Mopar. And all three are different. One is P/N 3614824 the head gasket that contributes to the infamous over heating problem (it has the three little slots for the water passages).

    In my other hand I hold the other two gaskets ‘pre emissions’ with bigger water passage holes. One is a genuine Mopar heads gasket and the other is a Felt-Pro. The size of the hole in the Felt-Pro gasket is even BIGGER than the Mopar gasket. Both of these gaskets are pre emissions. As a matter of research, I contacted my local Dodge dealer and checked on the Mopar gasket with the bigger holes (and I do have the part number), they no longer list it on their computers, and then they checked directly with Chrysler and again this part number is no longer listed.

    Again DO NOT match the water jacket ports. It may work but you are on your own and taking chances. Wait till I get the information compiled and then I’ll post it for all to see.

   

What we've found out so far:
 

   

Head Gasket Parts numbers courtesy of Mopar Chris, Gary Lewallen and my local Dodge dealer, who let me search though his parts manuals back to 1966.
    The P/N 3614824 for the 440 and 400 years 1972 through 1978 is a match for what is available now from Mopar Performance P/N 4286754.
    Of GREAT interest was the picture of the 8 cylinder gasket in the 1970 - 1971 parts manual.  IT HAD BIG HOLES.   If you happen to have a copy of the 1998 Mopar Performance Catalogue turn to page 98 and take a look at P/N 4120093 & 4120094 for the small block "A" engine, these are what the water passage holes look like on the picture of the 1970 - 1971 gasket.

INTERESTING???

From the information and physically seeing gaskets from prior years I feel I can safely say that in the 1972 model year Chrysler make a final and sticking change to their gaskets to help the meet the ever more restricting emissions regulations, and you as a consumer in the end are responsible to use the proper components in your vehicles.   As I said before I  have seen some of these earlier gaskets, and they do have larger water passages, what other changes Chrysler made in later years to compensate for less water flow in the head is for another study.  But, for me if I had a 1971 or earlier Mopar I would NOT just buy the same old heads gasket from Mopar Performance and stick it in my engine!!

A "small slot gasket" showing how little flow the head is going to get

A "big slot gasket" showing how much more flow the head will get