Pedros Techno DOF IMS fix?

[jb92563]

The IMS tube is not an oven and is the same heat as all the other oil in the engine so all this talk of burnt oil in the IMS tube does not make sense.

However, stale oil that gets into the tube and stays in there for longer periods could potentially be an issue if that oil does not circulate in a reasonable amount of time.

With the DOF installed I seems like there is a greater possibility of more oil getting into the tube and "circulating" so that it hopefully does not reach a degraded acidic stage.

To me this stale oil issue is a product of not driving the car enough, infrequent oil changes or both.

Like anything new, I suppose time will tell if there are any side effects, but intuitively, with a constant supply of filtered oil washing through the bearing with the DOF I would expect much better results than any kind of bearing replacement alone, and if its driven often enough there should never be any stale oil issues with the DOF.

I like this idea better than a bearing replacement as it solves the issue that causes the bearings to fail...lack of adequate lubrication with fresh lubricant and has the added benefit of keeping that bearing at a more consistent and cooler temperature as well, which should also extend its life.

[thom4782]

Structural weakness is the primary reason single row bearings
fail more frequently than double row ones. DOF, without bearing replacement, doesn't help this problem.

[jb92563]

Thom that is an important distinction which means that the Bearing upgrade AND DOF should be done together for those single row bearings as just the DOF alone in that case would not solve the issue.

Is there any data to confirm the actual cause of failure or are there multiple root causes in various cases?

Its hard to imagine that the Engineers decided to use a bearing that is not structurally sufficient for the loads encountered.

I'd sooner believe that the bearings fail for other root causes such as the acidic pitting, lack of proper lubrication, over heating etc, but I suppose human design error is also a possibility

[thom4782]

Data provided in the IMS class action suit indicated single row IMS bearings fail about 8% of the time whereas double row bearings fail 1% or less. Structural weakness is the best explanation for the difference in failure rates with all things being equal except the 1) the relative amount of contact surface areas of the balls and races of the two designs and 2) IIRC the thickness of the bearing support,

Even the dual row bearings, however, do fail so structural weakness cannot explain all failures. I believe compromised lubrication probably explains a lot of the rest and the 1% underlying rate. This phenomena happens when acids and particulates in engine oil causes bearing seal degradation that allows oil to mix with the bearing's grease. The combination lubricates very poorly and after some time the bearing fails.

[moresquirt]

THOM4782 based on all the info at hand,if u had an 06 thru 08 with the newer large single row bearing design that could not be removed without splitting the cases would u do the DOF mod or just leave it alone and change out the oil more frequent, especially at end of season before storage (if needed).

[thom4782]

I just don't know enough about the large single row bearing to offer a useful recommendation myself. With its low failure rate, I wouldn't worry and, if I did worry, I probably would simply change oil frequently.

The vendors sharply differ on the question of efficacies of splash oil (the IMS Retrofit website's oiling section) and DOF (the TuneRS site and Pedro's video). I don't know whether they would hold these same opinions when opining about the large single row bearing.

My car is a single row bearing and when I get to it I plan to install the IMS Solution.

[ppbon]

Originally Posted by thom4782

Structural weakness is the primary reason single row bearings
fail more frequently than double row ones. DOF, without bearing replacement, doesn't help this problem.

... that they fail because of structural weakness.
The reason, IMNSHO why they fail sooner than a double-row or the larger single row is because they have less surface area (between the ball and the race) and when the acid in the burnt oil starts to pit the surface it will fail sooner.
The bearing itself is strong enough to sustain all of the loads the engine will subject it to.
The problem, once more is the lack of proper lubrication.
YMMV.
Happy Boxstering,
Pedro

[Jake Raby]

fail sooner than a double-row or the larger single row is because they have less surface area (between the ball and the race)

This supports our point of view, that the problem IS the bearing.

And of course, there's still one very important fact concerning the 6204 bearing that no one has thought of, and its critical. Those who have attended my class know what it is, and they have held the bearing in their hand and manipulated it in two ways, then observed this critical factor. This is something I only share one on one and will never post anywhere. I am considered putting it into print in my M96 Engine Bible, but haven't made my mind up yet.

That single factor is what makes the difference. Every single Bearing Engineer we have consulted with has brought the point up, but we considered it before they did.

[stephen wilson]

Hmmm.... could be how it handles thrust loads?

[moresquirt]

Sure Jake,show the chrildren the icecream but don,t let them have a lick!!

[Jake Raby]

Originally Posted by moresquirt

Sure Jake,show the chrildren the icecream but don,t let them have a lick!!

The guys in my class today, here in Atlanta will learn about this tomorrow.

Otherwise its not shared or even spoken about. Plus, I want to see how long it takes the "expert opposition" that has attempted to join our ranks in the past year or so to finally figure it out. We've only known about it for a decade.

I am currently attempting to see if this was part of the discovery documents for the IMS Bearing Failure class action lawsuit. I'd be willing to bet that its not.

[Kirk]

Originally Posted by Jake Raby

That single factor is what makes the difference. Every single Bearing Engineer we have consulted with has brought the point up, but we considered it before they did.

So Jake... if we guess this super secret factor will you confirm if it is correct or not? I have seen Charles Navarro of LN state that he would take this secret to his grave!

I am going to throw out my guess and I am going to bet that I am spot on.

The issue is that in the design of the intermediate shaft the ball bearing application is compromised (not optimal) and the magic number (or constant) that it is compromised by is 20%. We state load numbers for the 6204 bearing based on manufacturer's numbers, but those numbers assume that the inner race of the bearing is turning. In most applications the inner race is fitted to a shaft through an interference fit, the shaft rotates, the inner race rotates, and the outer race is held in place in a fixed housing. Bearing load numbers are based on this scenario.

This is not what happens on the intermediate shaft though. That scenario is exactly the opposite. The inner race is fixed and it is the outer race that is pressed INSIDE the intermediate shaft that rotates.

So who cares if it's the outer race that rotates rather than the inner race? Engineers care because this one little difference has a significant impact on how much load the bearing can take. The general rule that is used in bearing calculations is that the impact is a 20% decrease in load. Decreased load effects calculated bearing life and failure rates.

Is this significant then? 20%? Damn straight that is significant. So how to address this? LN went to a stronger ceramic bearing with a much higher load rating than OEM. But eventually LN went to a plain bearing with significantly different load characteristics altogether.

So what do you say Jake? Do I get the gold star??? :dance:

Kirk Bristol

[Jake Raby]

But eventually LN went to a plain bearing with significantly different load characteristics altogether.

LN Engineering didn't...

IMS Solution LLC did. LN doesn't sell the IMS Solution, neither does Flat 6 Innovations.

[Jamesp]

Kirk,

Thanks for pointing out the bearing life factor. Do you have independent calcs on IMS bearing life utilizing the 1.2 factor? I'm deciding what to do with my IMSB right now and have not had time to do more than look up the 1.2 factor for rotational arrangement. I'll run the calcs later, but would like to see a second set to verify my work. This may have a big impact bearing selection.

[Kirk]

Originally Posted by Jake Raby

LN Engineering didn't...
IMS Solution LLC did. LN doesn't sell the IMS Solution, neither does Flat 6 Innovations.

So you are saying that LN and Flat 6 had nothing to do with the development of the IMS Solution??? Just because you started a LLC to cover your other businesses from liability lawsuits means very little if it is still the same people (George Navarro and Jake Raby).

Jake, you didn't answer my question though, do I get the gold star for exposing your super secret, the one that Charles was going to take to his grave???

I can see how this is significant. It should have had an impact on the class action suit against Porsche as their DESIGN is flawed and compromises the bearing! I can also see why Feelyx's idea got bought out for a patent. Yes, he was working on a direct oil feed system, but that's pretty straight forward. The main project he was working on was moving the bearing out of the shaft. He was focused on using a bigger bearing, but his design also moved the rotational point from the outer race to the inner race. I don't know if he realized that this one change would increase the life of the bearing by 20%.

Who has done an IMS change (New Oil Fed Design Idea) - Pelican Parts Technical BBS

Kirk Bristol

[cnavarro]

Originally Posted by Kirk

So Jake... if we guess this super secret factor will you confirm if it is correct or not? I have seen Charles Navarro of LN state that he would take this secret to his grave!

I am going to throw out my guess and I am going to bet that I am spot on.

The issue is that in the design of the intermediate shaft the ball bearing application is compromised (not optimal) and the magic number (or constant) that it is compromised by is 20%. We state load numbers for the 6204 bearing based on manufacturer's numbers, but those numbers assume that the inner race of the bearing is turning. In most applications the inner race is fitted to a shaft through an interference fit, the shaft rotates, the inner race rotates, and the outer race is held in place in a fixed housing. Bearing load numbers are based on this scenario.

This is not what happens on the intermediate shaft though. That scenario is exactly the opposite. The inner race is fixed and it is the outer race that is pressed INSIDE the intermediate shaft that rotates.

So who cares if it's the outer race that rotates rather than the inner race? Engineers care because this one little difference has a significant impact on how much load the bearing can take. The general rule that is used in bearing calculations is that the impact is a 20% decrease in load. Decreased load effects calculated bearing life and failure rates.

Is this significant then? 20%? Damn straight that is significant. So how to address this? LN went to a stronger ceramic bearing with a much higher load rating than OEM. But eventually LN went to a plain bearing with significantly different load characteristics altogether.

So what do you say Jake? Do I get the gold star??? :dance:

Kirk Bristol

This is just another piece of the very complicated puzzle. When we first started looking at this problem, the use of the bearing in outer race rotation was one of the first problems I knew exactly how to tackle. That's the reason for a ceramic hybrid bearing with sintered silicon nitride balls to be specific.

Jake and I have been using sintered silicon nitride for various components including lifters in pushrod Porsche engines primarily for their wear performance, but the added weight savings is huge.

Now consider the reduced mass of the ceramic balls and how that relates to the loads exerted on the races during the constantly varying acceleration and deceleration of the IMS bearing. This is even more important considering the load on the IMS bearing isn't even across the whole circumference of the races. Since the sintered silicon nitride balls are only 40% of the weight of equivalent steel balls, centrifugal force is lower - the lower weight of silicon nitride balls enables rapid accelerations and decelerations with reduced wear.

At any given time a very small surface area of the bearing is carrying all the load. To simplify what's happening, the balls are slung round 3/4 of the circumference of the bearing and they go from unloaded to fully loaded with only 1 to 2 balls carrying all the load. This is why we see flat spotting of the balls and skidding in the races leading to pitting and eventually complete bearing failure.

Integrated Reliability Solutions

Considering the bearing is in outer race rotation and already prone to skidding, this is just one of the reasons we chose against roller bearings from the very beginning and focused on ceramic hybrid bearings.

However, I will clarify that just going to a ceramic hybrid doesn't give you a higher load capacity than an equivalent conventional bearing but their benefits certainly outweigh the cost.

Hybrid Ceramic Bearings | Applied.com

PS. George is my dad. He used to work in the aerospace field in sales and he came to LN a few years ago to help my wife and I.

[Kirk]

Originally Posted by cnavarro

However, I will clarify that just going to a ceramic hybrid doesn't give you a higher load capacity than an equivalent conventional bearing but their benefits certainly outweigh the cost.

Hybrid Ceramic Bearings | Applied.com

Thanks Charles, the information you provided is very helpful!!!

I do have one question that has been bugging me. Looking at the Applied website that you provided you will see that they recommend grease first and foremost for ceramic bearings, but that's not practical in our application as the grease would need to be changed very regularly. In that situation they recommend oil lubrication and they note that a ceramic bearing does not need as much oil as a steel bearing. However, lubrication is still key. The LN Retrofit relies on oil bath and oil splash lubrication, which Applied notes is fine in some applications. However, they also note that oil jet and circulating oil are also acceptable.

So what if someone does not feel comfortable with the LN Retrofit approach? What if they think that oil bath/splash in this application of high RPM's and high heat is marginal and that a more consistent oil flow is better? What would be the problem with a direct oil feed to a bearing like the LN Retrofit? The LN Retrofit website discourages this practice:

"The LN Engineering IMS Retrofit kit should not be used with any forced oiling products for which they were not designed for."

But ceramic bearings in general are designed for all forms of oil lubrication. Since you are providing some technical detail regarding your ceramic bearing would you mind providing some better detail on why the LN Retrofit does not work with direct oil feed?

Kirk Bristol

[ppbon]

Originally Posted by jb92563

The IMS tube is not an oven and is the same heat as all the other oil in the engine so all this talk of burnt oil in the IMS tube does not make sense.

It's just a crock pot instead of a convection oven.
I have seen and smelled a couple of dozen cars in which the oil that came out of the IMS was as thick as molasses and stunk like nothing I'd smelled before.
We had to dissolve it with carb cleaner.

If you NEVER change the oil in your car it will gunk up and do the same.
The oil that seeps into the IMS is not replenished and that's why it's cooked.

Happy Boxstering,
Pedro