I am sorry if this has been asked before and I couldn't find it even though I used the search feature. Here is my question, in the 1960s were steel shim head gaskets used on 230-250 engines? My 1979 GMC with a 250 had a composite gasket as does the newer engines that I have now. My 1966 impala with a stock 283 had a steel shim type gasket. I am sure there are people on here who have tore stock engines down and could tell me if they were ever used. Thanks in advance Jay

Curious about your interest in this particular detail. The GM Parts Master doesn't shed much light on the construction of group 0.289 . . . save the 29-33 which is described as 'steelbestos' . . .
Old Car Manual Project . . . likely a composite including that infamous material.

Shim steel gaskets are not very user friendly. They assume new construction with straight and smooth mating surfaces. They also required special coatings. From what I have read the builder would spray the gasket with a special silver paint and then dust the wet surface with a fine aluminum powder. Seems awfully time consuming for an assembly line procedure . . .

Sheet metal gaskets have been around for ages. I've seen them used both in OEM and repair assemblies. It is true that they are a little more reliable when used on freshly machined surfaces, but I seldom had trouble when using them in other situations. In fact, I had one of the old Chevy 409/425 engines that came with two head gaskets installed by the factory under each head to lower compression. I removed the heads and discarded one gasket from each side and reinstalled the heads on the used single gaskets. The engine ran for several years without problems.

As to the use of gasket compounds, I always used K&W Copper Coat or spray High Tac. Never heard of any aluminum or other "powder" being used. seems to me that any granular foreign material would likely defeat the purpose of a clean surface and the gasket.

I HAVE seen silver or gold metallic paint used as a gasket compound in a pinch.

Blackwater knows the kind of gasket I'm talking about. When I worked in the Olds garage, those were the kind of gaskets used on Olds V8s. They were just sheet metal with a coating that looks like silver paint. We always sprayed both sides of the gasket with Red Hi-Tack. Never had any trouble. I just wondered if 230-250 engines used them from the factory or always used composite head gaskets. If they ever did use that type of gasket it would be an easy way to help raise compression. Jay

Most of the 60's engines I take apart have these. Impossible to find and very thin. I think about .018.

Every time I have seen these on ebay and in swap meets - they were sets of 4 for stacking two-each on the banks of a v-thing . . .

You've seen these on sixes?

So they did use them. Compared to now that would be like decking the block about .022. It's a shame no one can get one. Anyone used a copper gasket? Jay

I used them extensively when I was racing. There is some special prep and machine work required to use them successfully. The deck needs to be cut for wire O-rings around the cylinders for starters and we ALWAYS went to head studs to get more even torque when tightening the heads down. Some guys even groove the water and oil passages for O-rings!!

Some older copper gaskets came with O-rings around the cylinder openings and were stamped like the steel gaskets around other openings. My uncle, who was a machinist made a pair of copper gaskets for his '57 Black Widow Chevy when the steel ones wouldn't stay sealed. That little fuelie 283 was BAD and he knew how to make it run!!

What do you do if the block has been o-ringed for a steel gasket? The new gaskets aren't compatible.

Will Willis

Try a Detroit #55002CS.

I tried to look up that gasket, no luck. Of course my skills aren't that great. Near as I can tell it and another part number both cross over to a fel pro 1025. Jay

Summit and Jeg's offer dead soft copper gaskets. If you don't see what you need, go direct to the supplier. Most of them are custom made. I don't recall many steel gaskets being O-ringed. Most of those were stamped with raised patterns.

Incidentally, we only used the steel O-rings maybe three times before replacing them.