I got an NOS set from "SouthSide Obsolete" ("barnfind08" on here) a couple of years ago.
Those would be adjustable types. Ford never used the adjustable type in production. Folks out in the field liked the adjustables so a lot of NOS original non adjustables set on the parts shelves for many years. They still show up on flea-pay now and then.
How risky would it be to install previously used Ford OEM non-adjustable hollow lifters?
Is there a way of telling if they are too worn out to keep using?
Should they be flat across the bottom, concave or convex?
Can they be used ONLY with the original Ford cam that came with the engine at time of original factory engine assembly?
Or, can used lifters be used with another used cam?
Just curious.
1- You should NOT reuse old lifters. Some people have gotten away with it but
it is a recipe for disaster.
2- See #1.
3- They should be convex. Originals were spherical. Modern ones are tapered.
The cam lobe is tapered to match. This is to make the lifter rotate for
minimum wear.
4- After reconditioning, they can be used anywhere but should NOT be used on a used cam.
5- See #1.
For just abut everything we use these cars for, "NO". The only place they may have an edge is fuel economy, which would be so small you probably wouldn't be able to detect it.Is the 239 V8 flat head a better performer than 255 CID