I have a rebuilt motor done some time ago and not sure what has been done, it does run but I'm sure it can be better (I hope) any how with the plugs out I see valves that have the two dimples in the top, are these two piece?
You will have to remove them to know for sure.Unless there is some fibre optic thing you can look in there with. And there is, I just don't know how to tell you what it is.
Can you remove the manifolds and look inside or feel with your finger? There should be a lip with the two piece valve. Scott
With either the head or the manifolds off, you can see if they are 2-piece. No need to remove the valve.
Look through the manifold ports. Here is a picture. You can see where the valve head attaches to the stem. You can also see how the head can break. I found the pieces in my muffler. Glad it was an exhaust valve.
You can pull the spark plug and shine a flashlight and contort yourself and see if there's the infamous "two dots" to see if it's a two piece valve.
You can also see the stem swaged to the valve head if it is clean enough.
Replacement one piece valve on the left, original 2 piece on the right:
The original Ford valves say Ford on them.
The Ford logo that Larry mentions is on the underside of the valve head. Really hard to see when covered over with carbon however.
The two "dots" are holes for the valve lapping tool to fit. Not all valves with the holes are two piece valves. For example Model A Ford exhaust valves are one piece and made of stellite. They can be cut down to fit Model T with a bit of work on the lathe.
Thank you Royce, I do have some valves with the small holes in the face you say were for lapping but not necessarily indicating a two piece valve, I'll check this before putting much more time on the motor, I never want to find what Corey pictured!