Wanted F script GPW exhaust valve guides GPW6510

[wynnski]

Hello
Does anyone have any NOS F script exhaust valve guides they want to sell me. GPW6510

[wynnski]

.....anyone?

[dpcd67]

Now that's a detailed restoration; however: I have never seen one marked. Not saying they weren't. All I ever had and used, and that is a lot, were blank. They are made of iron and machined to size. Not suitable for stamping numbers into.
I have had plenty of F marked tappets and I just installed some in my F134 on my M606. Exhaust of course.

[wynnski]

Now that's a detailed restoration; however: I have never seen one marked. Not saying they weren't. All I ever had and used, and that is a lot, were blank. They are made of iron and machined to size. Not suitable for stamping numbers into.
I have had plenty of F marked tappets and I just installed some in my F134 on my M606. Exhaust of course.

They are F marked on the end of the tube.
They are made of something a lot harder than iron. If you break one getting them out they crumble after severe trauma or impact, it is some weird material.

[dpcd67]

That is cast iron. Typical reaction to impacts. That is how you remove them from the Dodge flat head; drive them down and smack them with a hammer, which breaks them in half, then drive the rest out; Not room for the whole thing. Cast iron is hard, but very easy to break. Which is why it is used for items that aren't subject to impact loads. And why they developed wrought iron, and steel.
Some are made from sintered iron with some bronze in the mix; essentially powdered iron.
Best ones are made from bronze but not for these engines. Copper was a scarce strategic material then. Steel would not be a good material for valve guides.

[wynnski]

I am still looking for F script exhaust valve guides and one more F script inlet valve