Oil Return tins

[Drew Pojedinec]

I haven't seen any comparison between these.
I have both the earlier and later style return tins that fit under the rockers.

I'm going to use them on my current 390 based project.
Engine will have a HV pump from Doug @ precision, so plenty oil will be flowing.

I'm cleaning up both sets.  Obviously I'll need to trim them for end stands and depending on which intake I end up with.

So opinions on which you prefer?

Thanks,
Drew

[gdaddy01]

I think it depends on the intake manifold you use . I had a set of the long ones and ended up cutting a lot off the drip ends to make them work . I did not know that there where two types at the time . THANKS FOR THE FORUM

[fekbmax]

I remember back in like 82 or 83 my uncle rebuilding the top end of his 69 fast back 390 / top loader and tossing those things and the valley tray into his scrap barrel.. Stuck him a solid lift crane cam and she'll lifters and a port o sonic intake with a 700 dbl pump.. That car ran its balls off. LoL.

[cjshaker]

I'd have to agree with the above, it depends on which intake is used. Some intakes will not accept the long style, which is what I'd prefer if I were using them. Honestly though, if the returns are enlarged and smoothed out, I don't think the tins do much good, if any. Sometimes they cause more trouble than they're worth.

[jayb]

The tins can be pretty important if you don't restrict oil to the heads.  The worst thing you can do is not restrict oil, and not run the tins; my testing on the dyno has shown that this rapidly drains the oil in the pan, causing it to collect in the valve cover area.  If you restrict the oil to the heads, you pretty much eliminate this problem.

I prefer the long finger tins, but as previously mentioned they will get in the way with some intake manifolds.  Edelbrock Victors are particularly bad.  The smaller  tins don't work as well, IMO, but are still valuable.  Both types often need to be trimmed to get clearance around aftermarket rocker stands, especially the end stands, which is one reason a lot of them ended up in the scrap heap.

[Drew Pojedinec]

Yup, planned on restricting oil.

Ok so gut feeling is confirmed:

1. Try to use long fingered tins
2. If those don't work, use later tins.

Solved.

Now to get these pesky interference threaded rocker adjusters to tighten up a lil bit and clean out the rocker shafts.....

[cjshaker]

One of the best upgrades I made to my 390 was ditching those interference fit adjusters and going to a set of the Crane adjusters with the lock nut. Only thing is, I don't know if they still make them. Whatever you do, DO NOT try and use threadlocker! I tried that the first time and the first time I adjusted them, that blue threadlocker turned to little shards of glass when it broke up from turning the adjusters. I had to disassemble the whole assembly and clean it. Hence going to the Crane adjusters

Personally, I don't like to restrict the oil to the heads much unless I find it necessary due to too much rocker/shaft clearance. Oil is invaluable to keeping the springs cool. Getting the oil back out of the heads and back to the pan quicker would be the better choice, but sometimes you just have to deal with what you have.

[jayb]

I'm not a big fan of the spring cooling theory for keeping oil in the heads.  In fact, if you look at the factory tins, they work to keep oil OFF the springs, not on it.  Unless you are running sustained high RPM, I don't think that the springs need to be cooled.  Some day I'm going to try to investigate that a little further with dyno data, by putting an IR temperature sensor in a valve cover, aimed at one of the valve springs, and running the engine on the dyno under different oiling conditions...

[rcodecj]

The tins are what .060 thick, wouldn't removing them affect your valve train geometry?

[Drew Pojedinec]

Yeah Summit has the Crane adjusters, tho back ordered a month (maybe they don't have them?)

I work with engines enough to know how loctite reacts in an engine   It an get nasty,  If we need to use something at work, we use a Loctite tape that does alright. 

For my usage, (street car with a random trip to the strip) I don't think I'll need the spring cooling effect of massive amounts of oil.

I imagine the tins do change valve spring geometry.... I would think it would be fairly mild, and if the pushrods are perfectly sized the amount of adjustment wouldn't throw things off too far.  Anyway, that is where I'm at in this project....  measure pushrods, get oil pump situated and pan made up, etc.  Mostly I just want to get the engine sealed up as my shop is on dust/grit restriction for the time being and it's annoying.

Drew

[cjshaker]

The tins are what .060 thick, wouldn't removing them affect your valve train geometry?

Yes, they do, to some degree. That's why it's always best, if they're going to be used, to mock stuff up before ordering pushrods. Lot's of engines built without doing it that way never have a problem, but if you want to be picky about things, it can throw the rolling point past optimum.

Some day I'm going to try to investigate that a little further with dyno data, by putting an IR temperature sensor in a valve cover, aimed at one of the valve springs, and running the engine on the dyno under different oiling conditions...

And Drew, I'm not arguing with you that you have to worry about heat, but just to bench race a little with Jay's theory about the effect on a higher demand engine. Heat always affects spring response, that's pretty much established in the science of the metallurgy. The final process of even making spring steel is based on a very specific heating process. But even at that, trying to show something on a dyno I think would be pretty hard unless you ran it for hours on end. Even then you won't really see the effects until it gets weak, or worse, breaks. Fatigue is the main issue, but heat speeds up the fatigue process.

I'd think it would be a better evaluation if a spring were tested, then ran through a cycle such as the spintron (the one where smoke was rolling off the rocker because of heat ) for lengths of time, then re-tested for pressure. But even that won't indicate lifespan shortening.

Like I said, if you can get the oil out of the heads on the end drains in a quick manner, then you don't have the filling problem and you get the benefits of cooling. When you ran the tests of the pan being sucked dry, it was at 6000+rpm. Did that engine have a deep sump pan? I can't remember. A drag race scenario requires a higher volume sump area just for that reason.

[jayb]

Nope, that test was with a stock pan, not deep sump.  What I would envision for a spring test would be to run the engine at steady state for 30 minutes or so at 3000 RPM, and see how the spring temperature compared to the oil temp.  Then, run several dyno pulls to 7000 RPM and see what the spring temperature does.  Probably do this on a couple motors, one with mild spring pressure, and one with lots of lift and high spring pressure.  I think that would give a good picture of how much heat the valve springs actually see.  Also maybe Bill Conley can chime in one this if he sees it, but there is some minimum temperature where steel starts to fatigue more quickly, and as long as you stay below that, you aren't going to affect the life of the spring very much.  Maybe somebody else knows about this?

[Drew Pojedinec]

Doug,
I know you were not arguing, hope I didn't give off a vibe that made it feel that way.
Just stating that for my usage, Street car with HV pump, I didn't think it would really matter.  I think there will be plenty of oil flying around up there even with some restriction.
Were i using a standard off the shelf pump I might have a different point of view.

For what it's worth, this is a decent powered 445, and I do cruise at 3000rpms (4.30 gears with GV).  This is my project "kick the 429 out of my Galaxie."

[cjshaker]

Well I'm certainly not going to argue any about more dyno testing!

[Qikbbstang]

"Devil's" Advocate:  LOL well we're taking about valve spring "heat".....just reach into your desk drawer and start bending a paper clip back and forth until it breaks - odds are you'll feel the heat generated in that paper clip by flexing it.  I once planned my visit to the Circle Track Trade Show to witness Smokey Yunick demonstrate his Smoketron Engine Testing Device a SBC, large elec motor and cut-away glassed over sections to observe the engines inner workings with the light of strobes. He encouraged us to get up close and observe the crankcase and the valvetrain. He had the retainers marked so you could watch them spin as the valves floated, I recall him indicating how valve float really heated up the springs and of course THAT heat further exacerbated the heat in the valve springs making for extreme valve float/rotation as spring pressures fell. It's a given that valve springs loose strength as they get hot.
    I don't have a clue about the heat building up in valve springs but I do know NASCAR teams use quick connects on the valve covers that run into tubing to precisely jet oil at the springs.
    My feelings are that max oil flow in an FE is essentially a set amount since the oil pumps bypass holds pressure to a given pressure.  I take it at max flow the oil around the rockers overwhelms the ability of it to drain through the heads and overflows the wall at the intake manifold and head. From what I can tell once oil starts flowing over the edge of the heads into the lifter galley it can't fill up any higher. So lets say it holds a quart at the flow over point in each head. To me you want oil at set amounts as much as possible. If there's a quart in each head, a quart in the lifter galley that makes for a given - it's like oil in a pipeline. It does not vary the oil level in the pan. You modify the heads drains to drain faster, restrict flow to the top-end and suddenly the oil in the pan becomes more variable
   What I thinks cool is the "Gods" that designed the FE were working with rubber umbrella seals on the valves --IF the oil levels in the heads exceeded the height of the valve guides* it was an oil burning nightmare.  Hence the flow-over point oil flows over has to be below the tops of the valve guides* This is a fixed point since the oil flow-over has massive capacity. Of course nobody runs "umbrella" seals anymore, but that does not change the architecture of there is only X much oil that a head can possibly hold. That is a fixed amount on the high side. Anything you do to speed up oil drain through the heads by enlarging passages or restricting flow is simply making the amounts of oil and oil levels variable. There's the conundrum you want to limit varying oil levels throughout the motor.
     The funny part is study a FE rocker set up the things got to leak like a sieve. The bad news is there are decidedly passages in the rockers and shafts that index to jet oil at the rocker and pushrod tips - you start restricting flow to rocker assemblies and the first thing that going to go away is those jets..   
 Remember the valvetrain's of FEs were never designed for .600" lifts with rapid opening/closings.