Original Style Split Valve Guides

old28

Senior Member
Does any one make the old original style split valve guides out of steel or is cast the only way you can get them?

I have seen them for a modern style valve setup, but none out of steel that are split for original style valves.
 
Brattons sells the cast guides individually or in a complete set. Have not seen split steel guides in the various supplier catalogs.
 

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Here is what I think, the cast iron ones have more gripping power along the joints allowing them to lock together. If they were steel, the edges would be smooth and better chance of sliding apart after installed. Also, cast iron does a better job of holding lubrication then steel.
Think about the Model A camshaft as an example.
 
I don't believe you will find steel valve guides.
Steel on steel is not a good thing with a limited oil supply. With parts that move against each other, it's always hard metal against soft metal. Hard against hard without a constant oil supply will seize.

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I do not know the answer, but I would not be surprised if it was a materials issue. The cast guides thermal expansion rates and how well it holds a size.
 
Thanks guys for all the replies. Good information, something to be learned each day. I think I will order a new complete set and install them. I had one brake apart, but I have no idea how old it was.

Is there a trick to installing the guide to make sure you do not crack crack it.
 
I used the split guides that Bratton's sells and found that when I put the two halves together the resulting hole in the middle was not round but was more oval shaped. Took me two sets to get 4 guides that were close enough to round holes.

Would not recommend.

YMMV
 
Grafe auctions is selling parts from Little Deerborn in MPLS. The final round is about to start and there are two boxes of valve guides. They may be all flathead guides, but it is worth a look. Maybe you can tell from the pictures.
 
In IMHOP split guides should stay together in the sets they were made in. It would be real hard to machine the guide one half at a time. They would be machined as a pair.
 
Steel guides are a very bad Idea for a Model A. The steel guide and steel valve stem will gall and the valve will seize in the open position. Don't ask me how I know.
 
Any recommendations on a supplier with good quality split guides? I know a lot are made in China. Not so good.
 
Modern valve guides are made out of cast iron. If you want to see just break one. The only other metal I have ever heard of guides being made of is bronze for racing. Not very long life, too soft.
 
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