I've heard of Ford HD 292 engines having exhaust valve stems that were sodium filled.  Cliff reported in another thread that the stems were ~7/16 in diameter, but I haven't seen any prior to this.  WoW!   

Click the link below to see pictures of the engine for sale on eBay with a cylinder head picture that shows the size of the exhaust valve stems adjacent to the intake valve stems.

http://www.ebay.com/itm/Used-Ford-292-V8-Engine-/112160346844?hash=item1a1d4712dc:g:5OsAAOSwOyJX9~cv


NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

They often have a cap on top of the valve stem that the rocker rides on. As I understand the Sodium filled valves have a tendency to break. Chuck

Y's guys rule!
Looking for McCullouch VS57 brackets and parts. Also looking for 28 Chrysler series 72 parts. And early Hemi parts.

MoonShadow, 292 w/McCulloch, 28 Chrysler Roadster, 354 Hemi)
Manchester, New Hampshire

   Broke one...steer clear of those.If they are new valves I don't think its a problem but when they sit the iron Ford valves deteriorate from inside out.At least that's what I was told after one broke/dropped one my 292.
     On the bright side the valves are so small they fly right out of the exhaust.
    Dave

I have a set of those heads so I went out and removed two valves. the intakes have .340" stems   .. They do have caps   on exhausts  the exhaust stems are .434".     The valve sizes are approx. 1 1/2 "  and 1 5/8 "  OD..  Hope this helps you..  This engine was from a 1962 Super -Duty and had Steel Crank and the Heavy Rods..   Steve McD

Mars , Pennsylvania

What's the benefits of using them?

Durham Missouri

They clear the carbon from the exhaust ports as the heads fly out


Gary - 1958 Star Customline and 1940 Ford Deluxe Hotrod

Ted redid a set of 471 heads for me putting thicker valve guides in to take the normal valves. Seems a lot of the decent low compression (supercharger) heads ended up on trucks with the sodium valves. Trucks are much more labor oriented and lower speeds. Although I don't really know why they did them.

Y's guys rule!
Looking for McCullouch VS57 brackets and parts. Also looking for 28 Chrysler series 72 parts. And early Hemi parts.

MoonShadow, 292 w/McCulloch, 28 Chrysler Roadster, 354 Hemi)
Manchester, New Hampshire

The benefits are/were: less weight, the sodium turns to a liquid and dissipates heat very quickly at less than 100*F, so theoretically reducing wear, longer valve stem life, and longer valve spring life.  Can run tighter stem clearances, less valve spring tension, which gets better gas mileage.  The problem with sodium filled exhaust valve stems in the FE fords was made worse by folks thinking they needed to increase the spring pressures to control valve float for performance camshaft changes.  Ford did not recommend going over 110# on the seat pressure even with high performance camshafts due to the light weight of the valve, and the tendency to pop the heads off from extreme seat pressures.  I raced a Medium Riser FE with sodium filled exhaust valves for many years and always kept the exhaust spring seat pressure at 110#, and the intake valves much higher depending on the camshaft.  Ran many a race at 74-7600rpms through the lights without a single failure of the exhaust valves.  Joe-JDC

JDC

Joe.  Thanks for the info about the sodium filled exhaust valve stems.  Interesting.

I'm scratching my head about how they were produced.  I imagine that they were expensive to purchase...


NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

Some time ago I bought a booklet from the Crown Victoria Assn on service bulletins. One way of disposing of them recommended was putting them in a lake.

  Dennis in Lititz PA