Pros and cons of sodium filled valves

[frnkeore]

What difference it makes, I don't know but, Ford used sodium/mercury in it's 427 exhaust valves.

[cammerfe]

Some years ago, Brother Lon had Carl Holbrook do up a set of TP heads for the engine going back in  his '67 Mustang. Because he had them, Lon gave Carl a brand new set of NOS valves. We put the engine back together and got it running and set off to go to Carl's place for a look-over. Lost a valve head during the trip---all of four or five miles. Carl said that it was a known fact that a batch of valves had got into the supply chain that had faulty welds between the stem and head. The damage was significant.

KS

[oldiron.fe]

                                                                                                                                                        most of what i saw with sodium valves in the 60s/early70s --short /med circle tracks 3/8-1/2-5/8 mi   may have put a full+ drag season on a motor in heat/semi/and 25/50 lap race in one night --one night a car left a damper/hachet/and half the crank on the track !! at the end of a 5/8 back straight --               circle tracks were hard on the early 427s -  sideoilers - nascar wide steel cranks better rods  because   of nascar!   went faster but $$$ - the days of (stock stuff ) soon gone     most fe circle motors lived a longer life in WI with solid valves     --oldiron           

[Henrysnephew]

  I agree with JDC above:  I raced several m/riser combinations in the late '70s-early'80s with the hollow/sodium valves.  Was told by John V to keep the seat pressures down as the super light valve weights simply didn't need big seat pressure in order to control valve action (they ARE very light).  Never dropped a valve at 7200 through the traps, but I did spin my share of rod bearings until we went with 392 hemi journal size.
   When I gathered parts for my cammer build (around '84) I scrounged a set of nos OE SOHC hollow/sodium valves.  John sent them out for Zyglo(?) imaging (like an xray) and they tested good.  Went with them and ran them on the street for 30 years.  Around 2015 I finally freshened the motor after collapsing a couple of OE piston skirts.  I replaced the valves with heavy-but-beautiful Ferrera units at that time and I've slept better ever since.  Randy M

[frnkeore]

Carl said that it was a known fact that a batch of valves had got into the supply chain that had faulty welds between the stem and head.

The Ford drawing of the 2.19 valve, only shows a weld at the tip of the valve and also says that, it too is sodium filled, the same as the Ex valve.

The nominal wall thickness of the valve stem, is .037, with a .030 minimum. Note also that the interior finish is specified.