Ken, I think I may have sent you pics last year on this one. But I will look through my old pics and see if I can find them. Otherwise I will take a few new ones. Tim
I only have the gaskets for the 72-74. If there was enough interest, I can look into having the 71 reproduced.
I would have to disagree about no gasket for a 71. They used a gasket that's the same material as exaust manifold gaskets.
You may be correct, however, no car I ever disassembled had a gasket and I don't see why a gasket would be required. The stainless metal cup that the stat lives in becomes the gasket. Also, I don't see the part/part number listed in the parts catalog. No listing for exhaust manifold gaskets either.
OK, Here is the skinny on the gasket. A gasket is absolutely neccessary on a 71 455 as the bottom is wide open to the exhaust crossover in the intake where a 70 was cast iron underneath. Try not using a gasaket on one of these and you will have a loud ticking exhaust leak. Copper RTV may work for a while but will burn through over time. The original gaskets were made of REAL ASBESTOS! I have an NOS which comes with the steel cup and the gasket. This may be the only way to find a correct gasket. This gasket material is a bit softer than the exhaust manifold gaskets. I am an asbestos inspector so was not surprized to see this. If you have ever taken an original 71 intake apart you will find remnants of the old gasket that may look like just crums at this point but it WAS there. The Asbestos is about the best heat resistant material ever made for a cheap price. No one reproduces these. Not sure it the two little screws would make enough force to keep a harder gasket from leaking.
Her is a picture of the original on a 71 455 I am taking apart. The gasket is still intact. The NOS cup with gasket on it is nex to it. The NOS cup or "housing " as it is listed is part #1237084 listed as group3.750 but look in the parts book it is not there. It is listed under the 71 455 carb parts in group 3.725. The are two listings for the same thing Both called housing and gasket. The other number is 1239043 and is cheaper than the 1237084 so it appears maybe the gasket was available alone.
Dave, Thanks for the great information on that. I had the 72 thru 74 style gaskets reproduced years ago because I couldn't find any for my cars. Tim
I concur, Thanks for the info. I have scoured the parts book, illustration manual, assembly manuals, etc. and could not find a printed word regarding the stove or gasket. What is the group number and part number on the box?? I always assumed that the stove was metal to metal. Also, I'm quite sure that my intake stat pocket is cast-over and no hole or opening to exhaust gasses is present. I will have a look at it to verify soon. Thanks again, and in advance, Matt
I had them made through a guy in NY. They built a die to stamp/cut them using the best example I could come up as a pattern. I'm actually not sure if they are real asbestos, but appear to be fairly pliable. The material also is metal reinforced as the original material was. They do have the groove in the center of them, so as they are tightened down they will flatten out and seal.
Matt, all the group #s and info are in my post #13. Group on Box is 3.75 but it is listed in group 3.725 which is a very long group. It is listed under 455 Carb parts. It is called a HOUSING in the text..................It is not a Wives tale Factory did not use exhaust manifold gaskets. I have friend who is old time GM mechanic and I asked him why he was not using exhaust manifold gaskets and he looked at me like I was green.:eek2:
Dave I will gladly take that old part off your hands!!! Just because I need it BADLY is no reason for you to feel sorry for me!!! LOL
