ford  counted on the od oil change with good oil.most  owners did not listen and rocker shafts plugged up especially the far end from spill tubes.
my first y 55meteor ,272, I worked in a log camp shop. changed oil every month using goo quality oil 30wt.never had to even set valves till50000miles
 lesson learned regular oil changes with quality oil and filters.

meteor..early GMC 6’s feed the shaft rocker arm system from their front support stand and have a much larger over flow on the center one. I’ve raced these engines since 1975 with valve lifts over .500” at 6000 rpm and never had a rocker failure or problem on the other end from the feed and its 3 cylinders away. 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

I wouldn’t toss the tin plates. They could come in handy if you want to experiment with rocker geometry in future.

6 VOLTS/POS. GRD. NW INDIANA

with spill tubes in place  rockers and lubrication  suffer at opset ends of rocker shafts suffer from poor lubrication.even with deeper grove in camshaft. this becomes even more critical with high lift rockers and wilder cam grinds.i also discard the tin plates between rocker stands and cyl heads. most of the ys now have compassion  head gaskets which lift heads .040 the same thickness of the tin plates. now you have restored original rocker and pushrod geometry,

I agree, though I did do John’s ‘drilled Allen-screw/rocker stand’ trick to balance the flow (early 2000’s Y-Block Mag article?).  10 psi per 1000rpm is traditionally the accepted min. I would use 10W-40 though.  Circulation is still more important than pressure.  It’s my understanding, that no matter how sloppy the bearings get, as long as the oil coming in is faster than what’s leaking out…..

6 VOLTS/POS. GRD. NW INDIANA

I don't believe 10 psi at hot idle and 30 running is all that bad for an older street engine.  I would put some 40 weight oil in it and drive.  On another note.  All these fixes with the rockers and tubes are not necessary if you cut the cam oil grove to .030" deep on rebuild. Mummert does this to all his cams. My Isky cam had .018" from Isky.  After this modification, I worried I would have too much oil to the heads. As it turned out, all is perfect with everything stock. 

I know it’s personal choice but I like to see flow. I’ve massaged both cylinder head passages/troughs and radiused the block hole to help the oil flow. Tim McMaster has a You Tube on the flow with the over flows closed with is very educational to watch. 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Peeeot, I had the same questions on the overflow tubes.  I just installed a set of Mummert hi-lift rocker arm assemblies, and noticed he puts a set screw in the overflow tube hole.  I asked him about the claim of needing that overflow oil to timing chain and distributor area.  He dismissed that need and said there was enough other oil splash to lubricate these areas.  So, I know he was certainly more knowledgeable than me on these engines.  
Just thought I would share. 
Ralph

Just my take - if your getting enough oil up to the rockers, there isn't a need to pressure them by closing off the tubes, at least completely.  And yes, from what has been said here, the tubes do provide oil to the areas mentioned.  And I don't think blocking off the tubes will help much with overall oil pressure, although I might be wrong on this

.



54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Two questions about pressurizing the rocker shafts:
1. Isn’t the drainage from the shafts intentionally directed to lubricate the distributor and timing chain areas, such that elimination of that drainage would deprive the intended components of oil?
2. If pressurizing the rocker shafts improves shaft and rocker life, why was it never done from the factory? It would probably have been cheaper than installing the drain tubes, and the factory loves cheap!

Pressurizing them sounds like a good move to me, just curious about the above items.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive