NOS Ford valve question
 

I recently bought some NOS Ford valves. Some have an indented top with the Ford script on them. Some have a smooth top with a Ford script on them. A couple have no script but look unused. The valve on the left is one I got at a swap meet, has IN on the top and looks new. Could this valve be used only for intake valves? I am wondering if these valves are good enough to use in engines with modern gas and its additives. Any input on these valves would be helpful. BTW, I am building a stock engine, nothing special.
Rusty Nelson

Re: NOS Ford valve question
 

I used NOS ford valves in my engine and it works just fine on pump gas.

Mike

Re: NOS Ford valve question
 

I've seen some older repair pictures that had all the valves with the circular recess like the one on the left in your picture. That may have made lapping easier, don't know. Haven't read anything that says there's a difference between the intake and exhaust valves.
Mine were all smooth top, but there's a very good chance they had been replaced.
Would be interested in other replies.

Re: NOS Ford valve question
 

Years ago it used to be that intake and exhaust valves were made from different materials. Not knowing how old those valves are, I would use that one on the inlet. You have nothing to loose by doing so but maybe if you don't.

Re: NOS Ford valve question
 

I've seen Ford marked valves with the IN, X, and R. The IN and X valves were in the corresponding intake and exhaust positions and the "R: valves were scattered all over. I don't know what the "R" stands for.

Re: NOS Ford valve question
 

Valves with Ford Script are all stainless steel and in my opinion are superior to anything made today. The flat top valves were the first design of the stainless type. In the mid-late 1930's, the as-forged, recessed type was introduced. They are the same alloy and can be mixed in an engine, however, I like to use them in sets (all the intake the same and all the exhaust the same). One important note: when using stainless valves, increase the clearance for the exhaust valves ONLY to .015-.017" due to increased thermal expansion.

Re: NOS Ford valve question
 

When you manufacture several million engines the pennies saved on each add up, so when engines were new the valves were different in quality for intake and exhaust. As the cars aged it made sense in making valves for the replacement market to standardize so all are of exhaust quality, and are used for intake and exhaust.

Re: NOS Ford valve question
 

indented valves are intake and can only be used in the intake valve seats, they are heat treaded differently than the exhaust valves, they will quickly burn if used for exhaust valves ,flat top valves are exhaust valves and can be used for either intake or exhaust

Re: NOS Ford valve question
 

Indented FORD script valves are stainless steel and non-magnetic.

Re: NOS Ford valve question
 

I RE-DID a Lincoln Model K-V-12 where someone used Intake valves in the Exhaust, burned the CRAP out of them! Fortunately, we had a donor car & took valves out of it.
SAME car lost a piston pin retainer & cut a slot in a cylinder wall:eek:
With a machinests' help, we bored & sleeved the hole, WITH THE ENGINE IN THE CAR!!!
Bill Dangerous

Re: NOS Ford valve question
 

Ford model A parts list shows both valves w/the same part #, A-6505-A

Re: NOS Ford valve question
 

Learned the answer, to this question, 50 years ago in Collage.
I called Rusty with the answer,...we decided not to post anything,...looking for the smart
people. One sharp fellow, an engineer did answer..

If in doubt,...always use the non-magnetic valve (exhaust valve),..it's made from better
material, in either intake or exhaust. It will last longer..