FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: Drew Pojedinec on February 01, 2016, 02:53:21 PM
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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
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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
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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.
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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.
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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.
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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.....
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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.
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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...
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The tins are what .060 thick, wouldn't removing them affect your valve train geometry?
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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 :P 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
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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.
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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?
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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."
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Well I'm certainly not going to argue any about more dyno testing! ;D ;D
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"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.
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Jay JMHO the 30 minutes at 3,000 ,,,is almost funny on overkill... I'd think the spring temps would stabilize as fast as the motor itself does. ,,,, any effect of heat from the springs heating will be so insignificant to other factors throughout the motor - just one example being the exhaust gasses flowing in the ports, that small item can really put some heat into a motor. Compare a spring to an exhaust port..... You got to figure heat transfer's from the spring seat into the water jackets... For sure springs are pretty well isolated as far as their abilities to shed heat. You have metal to metal down into the head, through the oil and air as a mist.
I recall seeing the effect of heat on valve spring pressures (charts) though I have no idea where it was and had no luck searching web. When you think about it I'd think simply heating a spring up in a spring tester should show the loss per added heat?......
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?
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It's been a few years since I had my materials/heat transfer/mechanical design courses, but temperature is most certainly a factor in fatigue and is a variable in fatigue equations. That's about all I can say without whipping out a book or burning my brain's clutch up trying to remember those equations though...
Either way, things are a lot different now than they were 40-50 years ago. Spring pressures in the 60's were 80-90 seat with 200-250 open. Now we run 50-100 lbs over that even on mild flat tappet applications. We also don't use umbrella seals anymore, we have positive stop seals, Viton seals, etc. that do a lot better job controlling the oil.
On higher rpm applications, it's very common to see valve cover spray bars, and in Cup applications, it's common to see both the cam tunnel/lifter valley as well as the area under the valve covers flooded with oil. Now obviously, none of us here are talking about circle track or Cup motors, but I would hesitate to say that oil up top is a bad thing unless you can't keep oil in the bottom....
However, my point is that I'm often reluctant to do things "the way Ford designed it in the 60's" just because the engines that we build these days don't resemble the engines from the 60's.
FWIW, I've never used a drip rail.....or a valley pan.....or an oil slinger.
However, I do work the drains in the heads, and in some cases, I will use some kind of restrictor. Most of my engines now are oiled through the pushrods though, and the lifters meter the oil quite well in most cases. I also use the Milodon/Moroso pans that are 7-8 quart capacity.
Another revelation that I'm migrating towards is that in most cases, a high volume/high pressure oil pump just isn't necessary. I would base it on bearing clearances and the engine's purpose. I can show you some bearings that came back from a season's worth of drag racing, with 55 psi on the gauge...I would have reused them. Most guys want to see 70-80 psi on the gauge when they're in the gas, but pushing large volumes of oil at high pressures will rob horsepower.
As Jay pointed out, a high volume pump (especially without restrictions) will pull large amounts of oil out of the pan. If you're going to use a factory style pan with a HV pump, I would restrict, and run the windage tray with an extra quart of oil in the pan.
Drip rails will also play with the rocker arm geometry, so do your pushrod measuring with the setup you're going to run.
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Well I'm certainly not going to argue any about more dyno testing! ;D ;D
Sure is hard to, when SOME people happen to have a dyno in their garage :P hehehe
It's been a few years since I had my materials/heat transfer/mechanical design courses, but temperature is most certainly a factor in fatigue and is a variable in fatigue equations. That's about all I can say without whipping out a book or burning my brain's clutch up trying to remember those equations though...
I know the feeling Brent, I've wasted so much brain matter with engineering studies that aren't used.
I really considered using a standard volume pump, but I really like HV pumps, then running oil that is slightly thinner than typical. I know it wastes a slight amount of power, but it's decent insurance.
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Another revelation that I'm migrating towards is that in most cases, a high volume/high pressure oil pump just isn't necessary. I would base it on bearing clearances and the engine's purpose. I can show you some bearings that came back from a season's worth of drag racing, with 55 psi on the gauge...I would have reused them. Most guys want to see 70-80 psi on the gauge when they're in the gas, but pushing large volumes of oil at high pressures will rob horsepower.
How much horsepower?
Cause it's about .75 HP to drive a small pump and about 1 HP to drive a big pump.
That's what math says anyways.
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What math? Even viscosity changes can be worth 10-15 hp.
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Well I could show you, but you might burn your clutch out.
Here's a simple calculator for you.
http://www.wallaceracing.com/oil-pump-hp-calc.php
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My clutch was smoked a long time ago.
I'll refer you back to your own data from 3 years ago....
http://fepower.net/simplemachinesforum/index.php?topic=1211.0
(First thing I learned in engineering school was that theory doesn't always match the results....)
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What math? Even viscosity changes can be worth 10-15 hp.
Boy, I've never seen anything like that. Tried 10W-40 dino oil vs. 10W-30 synthetic once, zero difference there...
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Admittedly, I was talking extremes.....0W30 against a 20W-50 or similar.
Again, we have to speak in generalities here, each engine has a myriad of different variables that play into the equation. We can't apply the same factor to each engine or each scenario.....i.e. a "small" pump takes .75 hp and a "big pump" takes 1 hp.
Bottom line is that generally speaking, high volume pumps can rob horsepower and guys tend to focus on big oil pressure numbers (or big flow numbers) as being paramount. A lot of the time it's just not necessary. Sometimes it is, but a lot of the time, it's not.
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Correction
That's not my data.
I was just putting someone else's data into a thread.
My data is to run a windage tray and a HV pump.
Use a minimum of 10W40 oil and a really good filter.
Put a minimum of 6 quarts in the pan plus the filter.
If you can swing it get a bigger oil pan.
In all cases.
I don't believe the average FE guy should go with less.
We tend to use the engine in a spirited manner and even race on occasion.
They cost a lot.
I'll give up the 1 to 2 or as you say 10-15 HP (which I think is BS) for peace of mind.
You need all the protection you can get.
What's your data say Brent?
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Heck, the oil itself can cause enough drag to kill valuable hp.
Not quite the same topic but long ago we pitted near many of the top Ford Pro Stockers while at the Grove, sometimes Rockford and once in awhile US 30 when it was still open. My 16 year old helper bro' James had a real talent for getting the racers like Glidden, Nicholson, Schartman and their helpers to talk to him while I was servicing my SBF Ford dragster. He came back one time with this tale.
It must have been Kaase he talked to as we figured out later but just before the match race finals at the Grove, all the rear gear fluid was drained out and about 1 quart of tranny fluid (think it was ATF) from the Lenco was drained. When he asked what the heck, he was told that they needed every bit of parasitic drag out to win the last race....and they did. Kind of extreme but heck, it didn't hurt anything.
Btw, Schartman's gal was a absolute ten and a real knockout and when she walked through the pits, everything stopped! Hah!
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My data says that every engine can't conform to the same rules. Take a 428CJ with loose clearances and factory pan vs. an all-new, all-aluminum build with a 9 quart system. You can't make generalities with this stuff.
Data is data. You posted it several years back and it's valid. I see 5-8 hp swings there, which backs up the statement I made earlier (which BTW, didn't warrant a 60-minutes style investigation) that higher volume pumps rob horsepower. I also made the statement that not everyone needs 80 psi oil pressures and HV pumps and I stand by that firmly based on all the different engines that I have in circulation.
BTW, if you want to call my 10-15 hp estimate bull butter, then you can call David Reher and tell him....it was his estimate. ;)
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I finished rebuilding my 428 Cobra Jet last summer. It has original iron heads, with a POPs roller rocker and end stand system. I used 70 Holley Jets as restrictors, and also used the long finger tins. I didn't do any trimming on the tins. I did a test fit, then flattened the parts of the tins that were in the way by tapping them flat with a hammer and anvil. Seems to work just fine. I use 7 quarts of oil in a stock pan with stock windage tray. I use 7 quarts because of the message Ford put out that I found on the 428 Cobra Jet forum under oil level indicator in the component identification section.
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My data says that every engine can't conform to the same rules. Take a 428CJ with loose clearances and factory pan vs. an all-new, all-aluminum build with a 9 quart system. You can't make generalities with this stuff.
Data is data. You posted it several years back and it's valid. I see 5-8 hp swings there, which backs up the statement I made earlier (which BTW, didn't warrant a 60-minutes style investigation) that higher volume pumps rob horsepower. I also made the statement that not everyone needs 80 psi oil pressures and HV pumps and I stand by that firmly based on all the different engines that I have in circulation.
BTW, if you want to call my 10-15 hp estimate bull butter, then you can call David Reher and tell him....it was his estimate. ;)
R-M's take on some of these issues.
http://rehermorrison.com/tech-talk-67-the-hidden-cost-of-free-horsepower/
Btw, their entire series of engine articles is excellent reading.
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Well Brent when you get "your" all aluminum FE running you be sure to
let us know where that needle is. ::)
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I can't see an oil pump creating a flat hp draw across rpm.
I'm certain at 800 rpm vs 2500rpms vs 7000rpm it's drastically different.
In the case of my engine, lets imagine there is only going to be a 5hp difference in most situations.... I can live with that, If I was building a race car I wouldn't have started with a 4200lb car.
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I would think that once you are into the relief you have reached
max power draw and it would stay flat.
Bottom line is: All machines will fail because of a lack of oil.
Not too many because it's getting lots. :P
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R-M's take on some of these issues.
http://rehermorrison.com/tech-talk-67-the-hidden-cost-of-free-horsepower/
Btw, their entire series of engine articles is excellent reading.
That's a good article, and backs up some of the reading I've been doing lately on oil viscosity and engine wear. I've been running 20W-50 Valvoline VR1 for years, but am currently switching to 10W-30 VR1. I thought I needed the 20W50 because I normally run looser on the bearing clearances than stock, but based on what I've been reading that is not the case, and a 10W cold oil will far out-lubricate a 20W at cold startup, which is where most engine wear occurs anyway.
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Which one Howie? I've got 2 all-aluminum FE's in the queue right now. I'm willing to share dyno data with you, including both high volume and standard volume pump engines. I think I also have some pictures of some bearings from some bracket race engines that have come back for a freshen-up. That's the best data...
Not sure why you highlighted "your"....it's pretty well-established that I build engines for customers. Essentially they are mine until the customer lays hands on them. ;)
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Is running a HV pump in a mild street engine worthwhile then? I think I am still going to get the heads modified for a restrictor and also open up the return, but I'm not sure if the added volume is really beneficial.
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It depends on several variables. For the average street engine with a factory style pan and decent bearing clearances, I would have to say no.
I built a 482 for a forum member, BBM block, BBM heads, hydraulic roller, T&D rockers. It was designed for a towing application, to pull a 10000 lb trailer behind his '65 F250. It has a standard volume pump in it and works perfectly fine. That engine was done by 5200 rpm and has 60 lbs of pressure cruising down the highway.
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I would think that once you are into the relief you have reached
max power draw and it would stay flat.
Hrm, didn't consider that, seems to make sense, tho you are still spinning the pump faster. No matter, I'm sure it's minor.
George, my two vehicles currently run like this:
76 F100, 390 FE Standard oil pump. Hot idle 15psi, hot cruise 40psi, WOT 65psi
63 Galaxie 429, HV oil pump. Hot idle 50psi, hot cruise 65psi, WOT 85psi
I run 5w30 in both of them. Oil samples report zero issues whatsoever.
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this is smoking my clutch trying to keep up reading you's guys knowledge . but thanks for the info
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Is running a HV pump in a mild street engine worthwhile then? I think I am still going to get the heads modified for a restrictor and also open up the return, but I'm not sure if the added volume is really beneficial.
This is the real info you need to make an informed choice.
There are 6 Melling oil pumps that will fit on an FE.
The minimum you should use is the "B" pump. It will give you the 60 + psi that you would want to see.
It uses the same spring as the HV pump.
I believe the standard volume pumps about 22 gals/min at 4000 rpm
And the HV pumps 25% more so about 27.5 gals/min.
And you only have 7 quarts it a regular system so. ::)
And you will be swinging a long stroke so it's your choice.
M-57 STD Volume Yellow Spring 40-45psi 1/4" Drive
M-57B Std Volume Brown/Plain Spring 60-65 psi 1/4" Drive
M-57HP Std Volume Big Blue Spring 100-110 psi 1/4" Drive
M-57HV High Volume Brown/Plain Spring 60-65 psi 1/4" Drive
M-57A Std Volume Brown/Plain Spring 60-65 psi 5/16" Drive
M-57AHV High Volume Brown/Plain Spring 60-65 psi 5/16" Drive
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Which one Howie? I've got 2 all-aluminum FE's in the queue right now. I'm willing to share dyno data with you, including both high volume and standard volume pump engines. I think I also have some pictures of some bearings from some bracket race engines that have come back for a freshen-up. That's the best data...
Not sure why you highlighted "your"....it's pretty well-established that I build engines for customers. Essentially they are mine until the customer lays hands on them. ;)
I'll go down that track with you again Brent.
I doubt Jay wants me to though. ::)
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Jay, I wonder if you noticed that in that article, twice he referenced oil for cooling the springs as being essential?
I've stopped reading all the debates on oils, simply because I've got enough of my own experience to satisfy myself. I run 10w-30 in all my year-round mild street engines. You don't want anything thicker than a 10w for cold starts in the winter. If it's going to pull heavy loads or is built for street performance, I step up to 15w-40 because of the added heat and bearing loads. If it's a hot street engine or is being raced, in other words only warm weather, bigger clearances and very high bearing loads, I stick with 20w-50 for the cushion. Only one time in my life did I have bearing problems, and that wasn't oil related. I've never had wear problems of any kind that were associated with oil, only normal wear due to age. That's good enough for me, and I've driven FEs day in and day out, almost exclusively, for the last 30 years.
Why worry about 5-10hp (max) unless you're shooting for ETs such as heads up racing? The risk and reduction in lifespan on parts isn't worth it.
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Jay, I wonder if you noticed that in that article, twice he referenced oil for cooling the springs as being essential?
I didn't see that, Doug. Here's what it says:
" Lightweight racing oils are also formulated not to cling to metal surfaces, reducing drag on rings and other internal components. "
" Thin oil doesn’t adhere well to the valve spring coils, so the resulting high temperature affects spring life. "
The oils we are talking about are not the "sewing machine oils" that he is describing, and certainly they will cling to the spring. He is also talking about 10,000+ RPM Pro-Stock engines, with over 1000 pounds of spring pressure on the nose of the cam. Which I think is also outside the scope of our discussion.
I have seen claims made that the valve springs on a normal performance FE should be running in a bath of oil for cooling purposes. I'm not buying it, and I don't think, after watching the oil splash through my clear valve covers on the dyno, that even with restrictors in the heads, there is any lack of oil on the springs. Restricting oil to the heads keeps it in the pan, and I think that is far and away more important than any valve spring cooling considerations, even on a high horsepower FE.
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I'll go down that track with you again Brent.
I doubt Jay wants me to though. ::)
You're right about that, Howie ;)
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can read that stuff on the other forum
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Is a real issue as far as I'm concerned. They use a valve cover spray bar to cool spring in some applications but even a Drag car has the need for cooling oil. On my 454, I was having problems getting enough oil to the right front and left rear rockers to the point of burning up pushrods. These are the ones farthest away from the oil feed into the heads. Never did come to a conclusion why but eventually got enough oil there to save the pushrods.
After a season while checking valve spring pressures the only ones that came in low were the end pairs under the low oil spray. That's telling me something. As for the pressure argument, I doubt we'll ever get a consensus on that but I'm old and like to see good numbers on the gauge. I'm willing to give up some HP for that warm fuzzy feeling. :)
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On my SOHC, the intake valves stick nearly straight up, at the top of the head. The oil runs away from these springs. The springs are around 270 on the seat and 750 over the nose. I don't ever see a difference in the intake springs vs. the exhaust springs when I check them.
Color me unconvinced...
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I will step into this - but very carefully. With waders. And stay very close to the shore....
Any time you are generating work - be it flow or pressure - you are using power in order for it to happen. The builder for a pretty well known Super Stock car once confided to me that a standard volume pump was worth 9 horsepower over a high volume one. I cannot recall ever running a back to back comparison on that, but it feels on the close/high side of "right".
On my personal engines I run a standard volume oil pump. On most customer engines I run high volume pumps. Much of that is due to perception. I can absorb any risk from "low" oil pressure, but my customers like to see a larger number on the gauge. It's one of the few things that an average person can see that provides a window into the function and health of the engine, and the general feeling is "bigger is better". Most of them would cringe if they saw 52 pounds at 700 HP and 7000 RPM, yet my personal engines live there all the time. Not only can I re-use bearings in my EMC engines - I do. Often.
I consider oil pressure to be a "gotta have some" kind of value and not a true indicator of durability potential. The pressure we are reading on the gauge is the supply side, the pressure supporting the critical rod and main bearings under 1500-2000 psi loads is largely generated by the bearings themselves as they rotate. Provide the bearing enough oil to offset clearance leakage losses and provide cooling and let the bearing designer take it from there.
The rocker tins are extra drainbacks - directing oil leaking from the rockers into the valley. Takes a lot of the flow away from the end drains. Unfortunately they don't work well on many aftermarket rocker systems. Remember that the original engine was designed around crappy, filthy oil at really low RPM for a very long time. We live in a different world with our builds now, and really do not need that much flow or drain area anymore. Use them when you can, but don't feel bad when you can't.
Volume is rotation of a given pump cavity moving a given fluid at a given RPM working against a given orifice. A change to any of those "givens" will change the system. Pressure reflects the area of the orifice as a restriction to flow, and will rise with RPM. Any time you change the size of the orifice, the pressure will drop. The orifice in an engine is the total of all the clearances in the complete package, some are not as obvious as it may seem. Rods, mains, cam, lifter to lifter bore, rocker to shaft, valve lash all have an effect. One of the clues in identification of a valve float condition on dyno is to watch oil pressure - it will fluctuate if you lose valvetrain control as the parts uncouple.
If you are doing things - or tolerating things - that increase flow through the system, a high volume pump will mask the condition and help put a better number on the gauge. It may mean absolutely nothing to the function, but it does certainly feel nice to see 20 or 25 pounds at idle on a hot day...my personal engine might scare you...
I went away from the 20W-50 a long time ago after seeing a modest, but real power gain from running lighter oils. In the contest stuff we are running 5W-20, but I still have not fully wrapped my head around using that every day - and I use 10W-30 most of the time. Like the standard volume pump - the gains are single digit. But find 5 horsepower in 10 places and you're doing pretty darn good.
I have not seen any power on the dyno with a windage tray - I have tried that one. But its still likely valuable in a car with acceleration dynamics, and I use them often. I have definitely and repeatedly found power in getting the crankshaft up and away from sump oil. Every time we have made the pan volume larger and deeper we have gained incremental power. The best pan on a dyno is probably a bathtub or a 55 gallon drum.
Valve springs do make their own heat in operation. But its pretty modest in the environment most FE engines run in. Spring oilers are important in Cup motors that run 10,000 RPM for four hours, but not a real benefit for something at 6500 RPM for 10 seconds. We have enough spray and mist in the covers to keep our springs pretty comfortable - remember that Cup level stuff is also vacuuming every possible bit of pressure (and oil mist) out of the crankcase with the dry sump. A very different environment. Sometimes we need to separate the visible problems caused by supply issues - bad parts, tolerance stacking, debris - from the system design issues or opportunities..
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well said , thanks
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+2
Very well stated.
Thanks