There's more to it than just the "so-called" pump volume rates.   

    Scott.

      The availability of "professional" quality hand porting work 'is' one of the casualties of this so-called modern era!  As this is laborious, dirty, noisy, menotonous and even "bad for your health" type work;  and then that only some possess the finesse for, and even fewer that will develop the skill, that will allow them to produce a truly professional result for.  So it just doesn't sound like a calling for the young people of today.  Then aid in that it doesn't even pay well!   

      I've got literally decades of my life given to porting heads & intakes, cast iron mostly early on, as there literally weren't any aluminum heads for Fords, except the BOSS 429, relatively scarce FE and then some "really" rare Cleveland and of even 'greater' rarity 385 series (canted valve) stuff that you just 'never' saw.  So back then, with only the O.E.M. cast iron stuff being readily available, this meant that only with a set of well ported heads were you going to be competitive, therefore there was a greater incentive to fill this "need".  But now it's just mostly a "vintage whim" practice, or someone looking for a cheaper option than buying a set of more modern aluminum heads, but in any case no longer presenting the "requirement" as in the past.  And then, as soon as you try to get paid a reasonable sum for the many hours of time you've invested, not that I even considered porting work as truly profitable in the shop, but rather just something that had to be done, first thing you hear is:  it'd be cheaper to just buy a new set of (chinese) heads off ebay!   

     Would you suggest to your child, that this might be a good career choice!   

     Scott.

I can feel a drag against the solid spacer or rocker stand, I'll let it fly. I've never seen galling when a slight drag is used.

       Remember, that in the O.E.M. configuration, the springs on the shafts push the rocker arms against the stands creating a certain sum of "drag"; and though not perhaps successfully causing a complete sealing against oil loss at this juncture, it certainly inhibits "free-flow".   

A .060 restriction will flow a lot more oil than most folks realize with hot oil at 50psi.

       Yes,  the sum is quite great; and "ideally" not what might actually be required to actually "limit" oil losses for the rocker shaft array.   

In fact, I would say that the stock rocker clearances and tins could easily be considered a band aid of the day.

     Exactly!   

Have you ever used a Victor FE intake?  They don't have any provisions for rocker drip tins, . . . . . . .

        Yep sure have, since back when they were fist introduced, something like twenty years ago (+/-); and there's an abundance of aluminum (and if need be more could be added) to make drain-back provisions work just as Ford had originally intended, . . . . . . yep!  This is if you really wanted such?   

I mean, I guess I'm sorry that I don't consult with almighty Scott before I put a bolt in.

        It's too bad, but that in pretty much any discussion it always sooner or later leads to "someone's feathers getting ruffled"; and as it seems here (at least to me), for no real reason!  You seem personally affronted here, and I don't see any reason for it.  I have not called out anyone in particular for unsound practices, rather have attempted to remain attuned to the mechanical engineering aspect, solely for the purpose of "discussion".   

        And then of course, we have to have the other human behavior seemingly relevant here, that of being any time there might be perceived two opposed perspectives, bystanders must always feel the need to "pick a side", did you ever ask yourself "why"?  Damn, at our ages, I'm thinking we left the school yard behind a long time ago!   

        But hopefully, out of this melee, perhaps someone garnered something of value, and that even though it hasn't been via the smoothest of pathways, the Forum has accomplished it's purpose of attempting to be informative or sparked thought, to at least a degree.

        Scott.   

        P.S.  Oh yeah, about that bolt, remember: "lefty loosey righty tighty"!   

           

     I was referring to the "replacement" they are sending you.   

     Scott.

     I thought this was a "discussion" forum; sorry my bad!   

    But it seems to me, that just making declarations of "I've done this or I've done that", though may prove interesting, but never really provides possible explanations or answers, or even hypotheses, as of the "why" that process might actually have merit, this vs. the old adage of: "that's just how we always dun it!"  But yeah, the latter surely is easier! 

     It's sorta like:  Why are you doing it, if you don't know why?   

     And, it's not about "attention", other than perhaps an attempt to draw others into the discussion, whom might, even if only initially, be more reserved, but might also "actually" have something truly valuable to add to the "discussion".   

     Again, sorry,

     Scott.

      P.S.  Hey, I'd bet, that if reading a novel, your probably one of those whom will read the last chapter first!       Maybe?   

     

Passing oil to the pushrod tip, roller tip, spring oiler, etc.

     If I understand, your intention is that we "need" a generous (?) clearance value in order to facilitate the flow volume required for these addition points of lubrication?   

     If so, then for consideration don't both these additional points of oil emission function "better" with the advent of oil pressure behind them?  This to "squirt" the oil fluid, in order to jump the distance, as these junctures don't possess a "direct" mechanical oil delivery mechanism to bridge this (depending on the rocker arm product)?  And as the clearance sum about the I.D. & O.D. relationship circumferences increases isn't the result going to be a loss of pressure in this area?  And this particularly with the popularity in the use of oil "restrictors" being present, which will, if effective, be limiting the oil delivery volume (more so than that of the self limiting function within the rocker/shaft relationship by design) and hence causing a loss of pressure as soon as the area of leakage (clearance sum) supersedes the area of the restriction?  And at this point 'even more' clearance probably isn't really going to help!      

     In other words, the greater the clearance, leads to greater leakage rates, that which then one finds excessive and unacceptable, so then they choose to install restrictors to limit the oil volume passage and leakage loss at the rocker arm to shaft juncture, this resulting in that oil volume as being made available is insufficient to create any significant pressure (aka. no "squirt", not to mention other oil starvation instances!), and resulting in it just drooling out onto the cylinder head emanating from the lower hemisphere just beyond the point of the clearance narrowing where the shaft and rockers are attempting to contact one another at the bottom in their eccentric positioning, and the greater the clearance the sooner and lower in these circumferences that this is going to take place.  And of course also, the greater the difference in these radii (due to clearance sum) this will result in less surface area interacting and reduction in the oil film load carrying capacity.   

     Or perhaps something like that might sorta be what I'm thinkin'.   

     Scott.

Depends on the application.   I've ran .002" multiple times........

     Well yeah, intentionally sure, "in certain applications" or even just rationalized for reasons that have nothing to do with the mechanics of it!  But in general, and consider the similarities, and the dissimilarities, and think about it.  Why are we "wanting" to have .002" clearance? 

     It's just a question.   

     Scott.