There are many different bearing designs. They each have their advantages and disadvantages. A hydrostatic (oil pressure fed) plain bearing is hard to beat in that the wear surfaces rise off each other and run on a film of oil. This is dependent upon bearing wear surfaces fits, tolerances, and geometrics along with lubricant pressure, flow, film strength, viscosity etc. The trick is to get appropriate oil flow to this location.

Rolling element bearings will have point load contact areas and won't be hydraulically supported to the degree of the hydrostatic plain bearing. You will have more time with metal on metal or ceramic. Without suitable oil feed a hybrid rolling element bearing is your best option. Theoretical cylindrical rolling elements would be a logical choice but they are not yet readily available and harder to make. They will also suffer if there is a thrust load component. Ceramic rolling element balls are now very common and are the standard in poor lubrication environments. Even prior to cermics ball rollers seemed to be favoured in bad conditions even though their load capacity was lower than cylinders; this is something I have found not always to be the case.

One just has to look at the other end of the IMS shaft for proof of concept. If there is suitable oil flow available then the hydrostatic plain bearing will the best option in this case

Oh just wondering if there's a new product in the works for 2005+ engines where the the outer seal is removed and then and then hit with an oil feed....A Cayman owner friend of mine would want to know.....not for me

I am riding on a ceramic dual row from a while back

Here is a Master Lube engine pre-oiler. It is used on vehicles to pre-oil your engine before starting so as to prevent "dry starts".

http://986forum.com/forums/uploads01...1361123768.jpg

It took months for someone to say that... And guess where we took part of the design characteristics from?

We've NEVER seen the plain bearing end of the IMS wear... Never.

The first post in this thread is about exactly that:

Direct Oil Injection for IMS Bearings | TuneRS Motorsports – Porsche performance, repair and restoration

Regards, Maurice.

Let me add several thoughts to the discussion...these are my opinions based on my reading the wealth of IMSB discussions in this forum and on others. I am not a parts developer nor am I an automotive engineer.

JFP described the nature of the IMSB problem well in post #26 in the following thread: http://986forum.com/forums/general-discussions/43117-excellence-say-just-remove-ims-outer-seal.html. When the seal on the stock bearing leaks, it allows a small amount of oil into the bearing area that mixes with the grease. The oil flow into and out of the bearing area isn't sufficient to completely wash out the grease and provide lubrication and cooling to the ball bearings. When this happens, the bearings degrade and the IMSB fails. As such, removing the seal and cleaning out the grease improves the longevity of the IMSB because the splashing of oil provides enough oil to the bearing surfaces to lubricate and cool them.

The direct oil injection part that started this thread recognizes this phenomena and it does two things: it requires removal of the seal and it feeds oil directly onto the bearings. It's advantage seems to be that it puts more oil onto the bearing than provided by splash oil. How much of an advantage is unclear to me.

The LN Retrofit is an unsealed ceramic bearing. It's extended longevity over the stock bearing comes from the fact that it is splash oil lubricated and uses ceramic balls. And as others have said, the ceramics last far longer than the stock bearing.

The IMS Solution is lubricated by pressure fed oil and it eliminates the ball bearings entirely. Its big advantage at least to me is that it eliminates catostrophic engine damage if the bearing should fail.

If I had to guess which combination of product offers the best protection, my ranking from most to least is:

1. IMS Solution
2. Direct Oil Injection with LN Retrofit installed
3. To close for me to call: Direct Oil Injection with unsealed stock bearing versus LN Retrofit alone
4. Unsealed stock bearing alone
5. Sealed stock bearing

What do others think? Does my explaination make sense. If I'm wrong, please weigh in so others have the best information available to them as they try to address their IMSB concerns.

I agree with most of your summary, thom4782.

My primary issue with "The IMS solution" is that replacing the ball bearing with a plain bearing may have unintended side-effects. The bearing type has an impact on the system. For example, a plain bearing is less efficient, which means that there is consistently more load on cam chains and the IMS teeth. I don't claim to fully understand the physics but I do know that unnecessary changes are a bad idea by definition.

In cases where the stock bearing is properly lubricated it has been shown to last over 200k miles with no significant wear. Since the chances of failure in a pressure-lubricated ball bearing setup go down to virtually nil, the risk of causing other problems by changing the bearing design suddenly outweighs the possible benefits.

Idling a car for a long time is an interesting but it is not a true test of the known-failure conditions. For example, it is known that unlubricated startup is one of the most stressful times for a bearing (and double that concern for a plain bearing). There is no reason to believe that temperature was a significant precipitating factor in the bearing failure. In the very worst cases, it took at least 30k miles of varied driving and multiple starts for the bearing to fail.

I suspect that we will find out what the new failure modes of "The IMS Solution" are in a few years when the first ones start to fail.

If you want peace of mind, choose a solution that is extremely reliable (oil-fed bearing) over one that is more likely to fail ("The IMS Solution"). In the absolute best possible failure scenario for "The IMS Solution", it is still thousands of dollars to repair. In the worst, it's still replace the engine time.

No, This is why it has taken years to develop. The technology is not new, My 300,000 mile Carrera shares the technology along with every Mezger powered 911 on the road.

Speculation thats totally off base.

There is nothing to fail. If the unit ever begins to wear the engine just picks up a noise that may exist for a very long period of time. The unit does not incorporate components that create collateral damages. Any wear materials that would be generated are non-ferromagnetic and not hardened tool steel like races and balls found in the ball bearings that do so much damage.

In testing we have forced units to fail and we know what occurs. I have documentation of these and on one occasion I cost myself 4,400.00 in less than one minute when we forced an engine to fail at 7,200 RPM. We utilized our special puller to extract the failed Solution and replaced it without engine disassembly and testing continued with no ill-effects.

We have even purposely contaminated the oil supply to the IMSS to know what occurs.

Been there, done that and have the experience, documentation and pictures to prove it. We have put the IMS Solution up against every challenge possible during development because developing components and manufacturing solutions are exactly what we do.

Did you fail to read that we cold started an engine 5,200 cycles and found wear to be immeasurable? Cold start has been our#1 concern since day one, but cold start doesn't inhibit the opposite end of the IMS that is ALSO A PLAIN BEARING from being one of the only portions of the M96 engine that we've never seen wear or break. Thats right, the opposite end of the IMS is supported by a plain bearing on every M96/ M97 engine ever built and it was NEVER the focus of a revision. If a plain bearing supported IMS was a problem the opposite end of the IMS would see failures, but thats simply not the case, because it simply isn't an issue.

This wasn't something that was dreamed up over night, the IMS Solution was "invented" the very first time that I disassembled an M96 engine. Why? Because a ball bearing in that position has never made any sense to me. Remove the ball bearing and remove the failure- Period.

Like I said, I invented this for my engines and thats the only reason. If another unit is never sold outside my engines I really could care less, because that means that we are the only company in the world that produces these engines that don't have to worry about a ball bearing killing the engine that has our name on it. I had to be "convinced" to allow these units to be sold outside my engine program, which is why we have worked so hard to patent the technology and have taken all the necessary steps to do so, including working in total secrecy for years.

Notwithstanding the fact this statement already constitutes a valid, enforceable guarantee, why would this not come with a written iron-clad guarantee against any failure of the IMS bearing?

A written guarantee would instill a lot more confidence than the claims of testing ad nauseam.

Keep in mind that guarantees, even those of proven products, routinely exclude negligence, lack of proper maintenance, damage from other causes, etc., and those reputable companies manage to function perfectly well in the marketplace.

Regards, Maurice.

OK, so when do you think the IMS Solution will be available for the 3rd generation, larger IMSB?

Jake - when can you post your test results and documentation to provide evidence so we can all move on and agree your solution is the best? Please don't tell me it's "proprietary". Flame away....

Either? Jake's solution has a cost associated with it.

Because here in the real world we know that collateral damage from other failures can easily kill the IMS Solution and it will never be conclusive when something fails. Nothing we sell has fine print associated with it and I refuse to sell people any product based on some shiny paper and a glorious warranty. I would rather fewer people buy our components for the right reasons, rather than selling them on a piece of paper and a promise. Its kind of like Unicorns and Rainbows covered with glitter, just like the rest of the modern world where over promising and under delivery is typical. I learned long ago that if I have to convince someone of something that they are not the type of purchaser that will appreciate what we create.

Remember, all I deal with are broken engines, nothing comes here healthy and its never a best case scenario. The Solution or any other device can be taken out by another device and then we have to prove that didn't occur- I don't have time for that.

That said, this thread was not started on the topic of the IMS Solution. Its unfair to the sellers of the "other" product to go off on such a wild tangent. They didn't do that to the threads that were started about our IMS Solution, so its not fair to do it to them.

Lots of good info in this thread either way. Everyone here should be glad that ANY option exists, people seem to forget that there was a time prior to my development of the IMS Bearing extraction devices when IMS bearings were said to be "non-removable" and if the bearing just started to fail the engine needed replacement. The fact that we can have these arguments about options is just a big pat on the back to me considering I built the first extraction device for 12 bucks and some scrap pieces from my machine shop. I should have patented it- biggest mistake I ever made.

Its been a good thread and I am leaving on a positive note.

That is good news. I have been thinking of picking up a 987, but have resisted due to the IMS issues. A solution to the larger IMS bearing problems would eliminate that hesitation.

Do you expect this project to be complete by 12/31/13?

Great read!! I have an 06 Boxster S with 60k and want to keep it for a very long time so adapting an IMS fix is definately on my bucket list.Jake Raby,your the man,and thx for all your work ,support and incredible design work because waiting for Porsche to help is obviously not in the cards.When do you think the IMS SOLUTION will be available for the 06 thru 08 late design IMSB.I have not needed any clutch work as off yet but was considering a comment you made on another site regarding just pulling the outer bearing seal which would at the very least lube the bearing if the seal failed.Could you comment on why the feed line location that Tuner Motorsports uses was less than ideal for the IMS SOLUTION.Thx
Warren H
Ontario,Canada

It already is, but only for installation here at our facility. While the fitment requires full engine disassembly, thats nothing at our level. We can turn the engine around in 3 days start to finish.