bennymac

I know that the 455 has oil issues. My question is if I'm building a street motor in the 450hp range should I worry about my oil flow? Do I need to upgrade from stock?

Oldsguy

This is how I understand it. If you change to a high volume oil pump without also making some changes in the heads for more efficient oil return and without increasing the oil system capacity (like a toro or aftermarket pan that is deeper), then you might have oil issues. But if you don't change to a high volume oil pump and don't rev the engine above 4500 to 4800 rpm then you don't have a problem. I didn't on my street driven Delta with a 455 in it on a mild street build and it is fine. BTW it maintains 50 psi at highway speeds and drops to about 30 psi in gear at a stoplight with the engine hot. No problems.

joe_padavano

Don't spend a lot of money on a Toro pan, it isn't all it's cracked up to be. In particular, the forward sump doesn't fully drain, so while it may hold a little more oil, the extra oil isn't necessarily available at the pickup. I've also seen large asking prices for Toro pans. Just spend the money on a good aftermarket pan, pickup, and high volume pump.

bennymac

thanks for the response.. if all the stock oil system can handle 4800rpm then i think i should upgrade. i'm running 3.73gears so the rpms get up there on the highway. i was looking at the mondello 7qt. oil pan, the full length windage tray and the main bearing oil restrictor kit. i'm just wondering if i need to drill an tap the lifter bore oiling holes as well? please tell me if this is total overkill for a street rod? i definitely don't need to be spending money on parts i don't need..

joe_padavano

Olds motors send oil to the lifter galleries first, then the mains and then the cam bearings. The popular restrictors that go in the cam bearing feed passages do almost nothing to restrict oil to the top end. Putting restrictors in the lifter feed holes WILL send more oil to the bottom end.

70Wcars

I am running the Moroso 7 Qt. pan in my race car with the HV pump and larger pickup. Turns 5700 with no issues and over 250 runs to date. I just run 6 qts. of oil but I am not a fan of the windage tray, some guys have reported the flat tray will collect oil on top and restrict drain back. This motor does not run main bearing restrictors. My street 442 however uses restrictors and a stock pan with HV pump and has been reliable for years with top rpm's around 5000 rarely. I did smooth and radius all the oil drain back paths in the heads and blocks of both motors.

88 coupe

Hi All,

1) Put in a pump that is able to move more oil through the pressurized system.
2) Add more reserve oil capacity, in the form of a larger pan.
3) Put restrictions in place to limit the volume the system can handle.

Or,

1) Put in a cam that will move more gases through the combustion process.
2) Add reserve capacity, in the form of a larger carb.
3) Put a restriction in the stock exhaust system.

How is there any difference?

Norm

joe_padavano

Big, big difference. Instead of "exhaust restriction", substitute "intake leak". The stock oiling system sends way too much oil to the lifters, up the pushrods, and into the valve covers. Putting restrictors in the lifter feed holes reduces this to only what is necessary for the valvetrain, keeping both volume and pressure higher at the rods and mains. In an oiling system, that's where you want the oil - especially if you have roller rockers instead of stockers.

88 coupe

Any more than is needed to cool the valve springs, would be too much.

Wouldn't that be the reason for using a HV pump?

But, don't you want it to keep moving back to the pan? If so, wouldn't it make sense to eliminate the restriction by increasing the bearing clearances?

If you have enough oil to service the springs, it would not matter what rockers are used.

Norm

joe_padavano

There's more to it than just the pump volume. Since the oil goes to the lifters first, the oil will take the path of least resistance. Sure, the higher vol pump will help, but at the expense of higher parasitic HP losses and the need for a deep pan.

Sending the oil UP to the heads isn't helping it move back into the pan.

Not true. The factory rockers slide on the bridge trunnions. More oil is needed to keep them lubricated. Roller rockers have less friction and lower oil requirements.

88 coupe

OK, we’ll put a restriction there. How did we increase pressure and/or volume at the crank?

How can it? With the restrictions we just put in place, it can’t pump any more volume than the OEM pump . Actually, at the same pressure, both pumps will move even less oil.

What losses? Not from higher pressure. We reduced volume. We did not increase pressure.

Yes, since we have restricted the flow, we will need a large reserve supply so we will not suck the pan dry.

My deep pans are for windage control.

Wider clearances at the crank will increase flow to the pan, and decrease it to the heads.

Not the issue. Valve springs need more oil for cooling than either type rocker needs for lubrication.

Norm

joe_padavano

Go stand in the shower with the water running. Have someone flush the toilet. You've now removed the restriction in the water pipe, DECREASING flow to the showerhead. When the toilet stops running, the flow and pressure at the shower head goes back up.

I suggest you get an illustration of the oiling system flow paths of the Olds engine. There's one such picture in the factory service manual. Oil flows from the pump to two main galleries that run alongside the lifter bores. Each bore has a feed hole from the main gallery into the lifter, and from there the oil flows up the pushrods to the rockers. Any oil volume and pressure that's left THEN flows down to the main bearings. If you put a restrictor in each of the sixteen holes feeding the lifters, more oil stays in the main gallery and thus both the volume and pressure to the main bearings is increased.

Think of the main gallery as a water pipe with a series of tee fittings. If all of the tee fittings are open, the water pressure at the far end of the pipe is low. As you restrict each tee fitting, the pressure at the end of the pipe goes up.


We reduced volume by installing a high volume pump? If you say so.


Sarcasm does not become you. Again, the restriction is NOT in the main gallery, it is in the side bleeds that feed the lifter.

Yes, that too.


Yup. It will also decrease the pressure in the oil film on those journal bearings, leading to both lower overall oil pressure and to premature bearing failure.

Uh, OK.

Look, at this point I give up. Believe what you want.

88 coupe

Adequate hot/cold water plumbing aside, it’s not a good analogy.

In this case, the feed pressure is not regulated to compensate for the difference. If (as in our oiling system) the pressure is maintained, the flow in the shower will stay the same.

Unless it addresses the pressure and volume differences we are discussing, it is a “red herring”.

How can there be more pressure at one end of the pipe, than at the other? How can there be more pressure, at the crank, than the pump is putting out?

If the pressure is constant, how can there be more volume if the total flow is restricted? If it is not constant, what could cause it to vary?

No. We reduced volume by restricting flow. If the pipe is smaller, a bigger pump will not increase the flow unless the pressure is increased. The pump cannot move more oil if it has no place to go.

As its name implies, the reason for the HV pump, is to insure adequate pressure when flow is increased.

If flow is decreased due to a restriction, even the worn out OEM pump will keep pressure up, because there is less volume to move.

It’s not about what I believe.

It is, about what everyone can learn from the discussion.

Norm

Oldsguy

I'm just going to post this link to help the rest of us reading this thread and trying to learn something and make some sense of it all.

http://www.answers.com/topic/pascal-s-law

As to what this means? Someone can open class again today for us...

joe_padavano

The fundamental problem is that this is NOT a static fluid and the oiling system is not closed container. Pascal's law applies to an inflated balloon or a can of spray paint that is NOT being sprayed. As soon as you press the button on the spray can the fluid is no longer static and there IS a measurable pressure difference from one end of the can to the other. Assuming the nozzle chokes the flow, the pressure in the can will eventually reach equilibrium at a lower pressure. This is an oversimplification and there are a lot of considerations like the size of the nozzle and the time history of the event.

As another (admittedly oversimplified) example, consider the oiling system as a pipe with a lot of leaks. The input pressure and volume is constantly varying with engine RPM and oil temp. At any given time, you can take a snapshot of the system, however. If you collect the total volume of oil coming out of all the "leaks", it obviously equals the output of the pump. If you make some of the leaks smaller (ie, put restrictors at the lifters) then the volume of oil at the other leaks (the bearings, for example) goes up. In NO CASE does the volume exceed the pump output, it just gets redistributed.

Pressure in a dynamic fluid system, however, varies with outlet area and internal flow friction in addition to temp and RPM. The static pressure (yes, that's a terminology issue since this 'static pressure' refers to a dynamic fluid) will vary depending on the area of the "leaks". For a given amount of leak area (and at a given engine RPM and oil temp), you'll get a given output pressure at each of the leaks. Since this is a dynamic and not static fluid, with internal flow losses within the system, the pressures at each of the leaks WILL be different. If you close down some of the leaks (ie, the lifters), you WILL increase the pressure at the remaining leaks since the total leak area is now smaller. Note, by the way, that at no time did I ever say the pressure would be HIGHER than the pump output, only that the pressure drop would be smaller. If you took this to the limit and closed off all the leaks, THEN you'd have the closed system that Pascal's law applies to (and you'd also have a higher static pressure than when any of the leaks are open).

joe_padavano

I lied. I am commenting. Sue me.

There is no pressure regulator in any normal automotive oiling system I've ever seen. Your oiling system DOES NOT maintain pressure or volume. Just the opposite - oil pressure varies with engine RPM and oil temp. There IS a pressure relief valve, but this isn't a regulator, just a safety device.

As I noted in my previous post, the design of the oiling system ABSOULTELY addresses pressure and volume differences. This is not a static fluid, it's dynamic. There are internal losses due to friction of the oil flow in the passages. There are losses due to oil being bled off at each of the oiling points (lifters, bearings, etc). As I noted above, while the total volume of oil in the system is a function of the pump, the RPM, and the oil temp, the DISTRIBUTION of that oil can be varied by restricting some of the "leaks" and forcing more oil to flow out the remaining locations. SBC motors feed the mains first and this is much less of an issue. Olds motors feed the lifters first, hence the problem.


The oil system isn't a "pipe", it's a sieve. There absolutely is higher pressure at the pump output than at the main bearings. Again, this is a dynamic fluid, not a static one. No one ever said there was higher pressure at the crank than the pump was putting out. One CAN, however, minimize the pressure DROP between the pump and the crank by minimizing the loss at the lifters. One can also minimize the pressure drop by improving flow inside the oil passages by chamfering corners, polishing galleries, etc. Same concept as porting heads and intake manifolds, only the fluid is different.

Again, the total volume doesn't change, but the volume directed to the crank WILL increase if less is bled off before it gets there.

I'm sensing a misunderstanding. I consider the "pipe" to be the main oil gallery (actually, two of them) that runs alongside the lifters. Nowhere have I ever said that we would restrict this "pipe". However, this pipe has a series of holes in it - one at each lifter - that allows oil to escape instead of flowing to the crank. If these holes are made smaller, more of the available volume will now flow to the crank. Your point would be correct if we had a closed, static system, but (at the risk of being called a broken record) this is not a static fluid system.


Funny, I thought the name "high VOLUME" pump implied that it was supposed move more oil at a given RPM. You are correct, however, in that the effect of higher volume is that the pressure drop at a given point will be less.

That's my point exactly. Of course, a worn out OEM pump may still not have adequate pressure or volume, but the restrictors in the lifters provide benefit to the crank in all cases.

88 coupe

At that pressure, yes.

If there is a rise in pressure, volume might increase slightly. But, not as much as it would (at the same pressure) with an increase in bearing clearance. And the plus, no change in pressure = no parasitic loss.

Especially when applied to the outlet area.

How much different?

Assuming the pump is capable of more pressure, at that RPM.

My mistake.

Norm

88 coupe

Yours is a more accurate statement. At or above its set pressure, it becomes a regulator. At pressures below that line, your arguments have been valid.

Only if the pressure can be increased by doing so. Once the max pressure setting on the pump is exceeded, it cannot.

And hence, this discussion.

How much higher?

My mistake.

Did all that, and much more, with my first 455. Didn’t help much.

If you were thinking: At the same pressure but through a bigger pipe, you were correct.

Not exactly what I said.

Might have been more clear if I added, “by increasing bearing clearances”.

I restricted my pushrods. Cheaper and easier. Didn’t help my first 455.

Norm

Oldsguy

I never thought of that one but it makes sense, if you are restricting the oil flow at the ports to the lifters or restricting the oil flow at the pushrods, it would seem to be the same effect, but, I guess to no positive effect in your instance. I think the solution for me would be to keep it below redline and just use the available torque at the lower rpms, seems to be enough for most street applications. I think I see the tendancy to "over build" the motors, and I am refering to almost everyone, not just we Olds enthusiasts. The majority of us don't drag race so I think we end up having too much money and time into our engines although isn't that what a hobby is all about .

bennymac

I'm not even sure I want to step back into this discussion.. My original question was for the 455 that I am building, although since then the current 455 in my truck has been losing oil pressure. What is the cause of this and what steps can I take to try and fix it, see how my other moter is still not ready?
I've changed the pressure regulator (if thats what it's called) to rule that out and I don't think it's a gauge issue, so I'm wondering what my next steps are?
The pressure seem to maintain for the first half hour of driving, but drops from a 30/50 to a 15/30 and it seems to do worse at highway speeds.
Could this just mean my pump needs to be replaced or is it the flow is getting restricted some where in the motor?

88 coupe

It’s been done, with hydraulics, since the sixties. Lifter bore restrictors have been used with solids for about as long. Pipe cleaners were commonly used to restrict pushrods until Mondello started selling his “store bought” versions.

For the $112 difference, I’ve always used the cheaper method and have had no problems.

On another note: Since the cam journals also get more oil than they need, a cheap and easy restrictor can be made by drilling a .07” hole, adjacent to the existing one, in each cam bearing, then installing it accordingly. Added plus, is that they won’t come out like those plugs have been known to.

Didn’t help, because it wasn’t the problem. Problem was tight bearing clearances, at the crank. Too tight for the RPM/power level they were being subjected to. How that came about, would be a different topic.

You solution is the same as for everyone. Set your performance goal, then spec the shortblock to reflect the changes you will make in the future.

Including me.

Norm

88 coupe

No reason not to. Your input is no less valuable than anyone else’s.

And that question is what we have been discussing. Hopefully enough information will be presented, that you can gain the knowledge to make your own choices.

Could be one of several causes. Since it is a separate issue, it should be in its own thread instead of being hidden under this one.

Norm

88 coupe

To elaborate:

When you order the crank kit for your rebuild, you can specify your own clearances. There is no extra labor involved, so, no extra cost.

Outside limits of factory tolerances (including side clearances on the rods) should be adequate to 5000 RPM in most street applications.

Norm

Kennybill

Question about 455 oil issues??

--------------------------------------------------------------------------------


Wow, when one talks oiling and Oldsmobile, look out, many different opinions! Oh ya, I too have my own. I had an a bearing "problem" with the very first Olds 455 I built for my Son. Was it an "oiling" problem, maybe. More of a "rear-end" problem. Here's what went wrong. G-body, lo-comp. 455, Hi-vol pan but stock pan 2:73 gears. Car ran strong, shifted 5200 rpms, no problems. BUT,,, you know how guys are, installed 4:10 gears. hmmm now problem. Within a day my Son says "Dad, the engine is making noise." He "whipped" it for 3 months with the stock gears that let it wind-up a little slower, oil returned just fast enough so the pan didn't dry up even though it did have a hi-vol pump. New 4:10 gears let it rev faster, sucking the pan dry. #5 rod bearing spun. So my opinion is, stock pan, stock pump, not to low of gears, rpm's under 5000, keep oil pan FULL, use a large filler. High volume pump, 7 quart pan, use lower gear, higher RPM's OK, within reason. Now I will stir up a "Hornets" nest. We are talking STREET here, not all out RACE or BONNEVILLE SALT FLATS. Toro Oil Pan SYSTEM, and it is a system that consists of a 5 quart pan(one more qt. than the Stock 4 qt pan) two windage trays, one near oil pump and one that blocks off the timing cover area. I "believe" there is LOTS of wind coming from a timing chain spinning 5000 rpms. The front tray blocks this area, good idea, in my opinion. Tray near the oil pump helps a bit. Now the dreaded Toro pan!!! I have tested pan at the same angle as a stock pan in a car, poured in oil the the EVIL front sump area, maybe a third of a qt at most stays in the front sump area. There is a small channel (not as deep as the front sump though) from the front to the rear large sump. To cure that MAJOR problem of 1/3 qt of oil, heat channel area and make it deeper. Not Rocket Science here, hmmm, maybe it is. Also this pan has a side crank oil scraper. Olds Engineers knew they had a "bit" of an oiling problem so they came up with this solution. They weren't stupid. These Toro's set Pike's Peak records plus they had up to 400 HP in 1970, I believe. So in "my" opinion, a modified Toro oil pan system is better than a stock 4qt pan. Hmmm, 6 total qt's vs 5 total qts, I believe is 20% MORE oil, this might make the difference between life and death for the engine. Also, I notice when I "floor" one of my cars the front-end raises up which would empty the dreaded front sump even if I hadn't notched the channel deeper. Remember, I am talking "Street" not a National Record Holder here. Plus if the Olds oiling was so bad, every "442" would have spun thier bearing within a month of leaving the show-rooms, hey they only had a 4 qt pan and one could get them with 5:00 gear ratio from the factory in 1970, ya, 5:00 gears in a 455. I know I will get flamed on this post. Even the front end of my 98 raises up a bit to let the oil drain. Later, Ken 3-14-2007-42.jpg

88 coupe

ROP would be a much better place for such foolishness.

Yes, we have been discussing bennymac's original question, regarding his street rod.

Race cars/race engines would be a different topic.

Insignificant when compared to the output from the crank.

Will it do anything to improve the windage problem, and its resulting HP loss?

Semantics aside, there has never been a problem. If there was, they would have known about (and addressed) it before it went into production.

Did they all come from Dealer showrooms with no preparation? Or were they "blueprinted" by the factory, especially for that occasion?

By themselves, net/gross/peak/rated HP numbers are all but useless.

And a 7 qt pan with 4 qts would be even better, because of the decreased windage.

20% more than is needed?

Can't speak for anyone else, but all I do is "drive anywhere" street/highway cars.

Isn't that what I've been saying?

Not likely.

Norm

Kennybill

quote, "ROP would be a much better place for such foolishness." Hmmm, usually every time I say anything good about the "Toro Oil Pan System" I get flamed on how it is NO good. So, I was saying jokingly, that I knew what was coming.
I think the Olds Engineers built the Toro to be a high-performance luxury touring car. There must have been a reason for the 5Qt Toro pan with a crank scraper and a windage tray plus the front block-off tray. I always thought it showed they were pretty smart and ahead of the times. I have a few of these Toro systems and for a street car I like them. Basicly I think we are on the same page on the oiling issue. I always say "a man needs to know his limitations, especially with an Olds." I say it as a joke but there is some truth to it. Ken

Oldsguy

Well. I am not going to worry about it on my 455. Again, I am no engineer, I am not even an experienced engine builder (much less an experienced Olds engine builder) so I will say this. Trust the stock configuration, be realistic, don't try to rev a big block like a 6 liter V-12 on steriods and just take advantage of the huge amounts of torque available from a BBO. I will be happy.