49 to 53 valve question

V848 Ford

Member
Did Ford use different steel alloys for the intake and exhaust valves or are they the same?

I have military surplus intake valves. Will they work for exhaust valves too?

Thank you.
 
They did in the early V8 years but by the 8BA days, there wasn't much difference. The military may have contracted any number of manufacturers to make them replacement parts from the OEM to aftermarket types. Modern replacements are pretty much all the same.
 
Did Ford use different steel alloys for the intake and exhaust valves or are they the same?

I have military surplus intake valves. Will they work for exhaust valves too?

Thank you.

No. If it says intake on it it was designed to operate at much lower temperatures than an exhaust valve. Exhaust valves are made from a more heat resistant steel. It would probably work for a while, Certainly not worth the gamble. If they were stainless aftermarket it would be ok.
Bill
 
In civilian usage Ford intake and exhaust were different...on assembly line only. At least for '32-48, engines left the Rouge with different valves but only exhaust valves (which were dimensionally identical to intakes) were available for replacement.
I once used a set of WWII surplus valves from Joblot, and all were exhaust.
Those suckers were packaged to survive storage on Guadalcanal, I think. It took me half an hour to carve each one out of a fat block of cosmoline with layers of cloth in it and get them clean for use!
 
If you ever look the old valves over real well, you can see the heads are recessed on the centers of the intakes and the the thickness of the area between the valve face and top of the valve head is more narrow than the comparable exhaust valve. The exhaust valves have no recess and are thicker but not by a lot. The early exhaust valves had stainless heads welded to steel stems. Many aftermarket valves that did manufacture them differently, actually have the letters "IN" forged into the head of the valve. Not stamped but raised forging marks. Exhausts will be marked "EX" by these manufacturers.

If you can tell they are intakes, then they were designed to work as intakes only. If they are all the same head thickness with no ID markings and they look to be pretty thick compare to the average intake valve, they are most likely exhaust valves and should be interchangeable.
 
Generally, you can stick a magnet to the head of an intake valve, but it won't stick to the exhaust valves. Don't test to the stem....as stated above, some mfrs used regular steel stems on both valves,but the head is a different non-magnetic material.
 
I just read the whole thread and was going to reply but Mac VP beat me to it. Just take a magnet, if it don't stick it's stainless and can be used for exh. If the magnet stick to the head it's intake. Walt
 
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