Jake replaced my IMS bearing LAST week

[mikefocke]

I said early on in public (and privately to Jake) I'd need to watch and see the number of cars done and their mileage before I'd be able to tell the success of the program. And I said this while pointing people to look at the Charles/Jake products/programs so you know I'm not anti..just skeptical as I feel we all should be of any maker/supplier's claims.

I was once responsible for producing a complex product and I know that testing a large number of units can reveal parts quality variation problems. And length of use testing/monitoring can revel suitability issues...in the case of cars, suitability over a wide range of conditions from 2 mile Walmart runs to racing, from Alaska cold to Death Valley heat, from every 3 months (!) oil changes to every year.

Lets use those numbers cited in the quote below and assume he has been doing these for ~10 months. 15 done. Average 1.5 per month. 82.5 estimated months of use. 2k miles per month. Translates to maybe 165k miles of testing. Pretty darn good. Especially considering that there are another 85 out there of some approximately similar longevity done somewhere else by someone else.

Consider that the IMS failures are normally at the 20k-60k miles point according to the way I read the stories and don't occur in all the factory units. We haven't achieved enough cars with IMS mods getting well through that mileage. We have more than enough units tested. But not in miles per unit tested. Once that number gets much higher than it now is, I think we'll be able to say for certain that the replacement design is better than the original. Until that time, the theory sounds good (and I'd go that route if I needed to) but my intellectual jury is still out.

This gets even more complicated because every car is different in the number of mods that get done to it and the individual mods change over time. So there are many combinations...many one of a kind.

And is the success truly perfect? We haven't heard of a single product failure, have we? (IIRC there was an engine that failed but it was not one of their products that failed) Is that normal?

And as for value added in the resale market by these improvements, I somehow doubt they will bring back much of their cost considering almost no other mods do. I've seen people say you get 10-15% back on the cost of your mods if you are lucky and sometimes the mods make it harder to sell the car.

Suppose the average potential buyer sees 2 cars advertised:
car 1: complete history, no major problems and no unresolved problems
car 2: major internal engine improvements to improve reliability

Is car 2's advertising confidence building or doubt creating? I know when I was looking for a Porsche, I originally thought of the 928 but the number advertised with very extensive rework told me this would not be an easy/cheap car to keep for a long time. So which car will the average buyer pay more for? Be looking at first?

I certainly wish the original thread poster good experience with his mods. And hope this discussion hasn't thrown too much cold water on his increased enjoyment and confidence in the reliability of his engine. I certainly think he did the mods at the right time when the clutch needed to be done too so the total expense was minimized. And he got a nice trip out of it.


Trust but verify.

Originally Posted by gschotland

Jake told me over 100 had been done and that mine was the 14th he'd done; number 15 arrived from CA the day I picked my car up.

[blue2000s]

Mike - Excellent points and I agree 100%. The only issue I see in your statement is that the 165k miles should be considered initial miles. In wear-type failures like the one we're dealing with, it's important to consider the individual component useage as opposed to the compiled component useage. For example, 1,000 cars with 10,000 miles each are less likely to give good statistical results in a wear out issue than 100 cars with 100,000 miles each.

Lifetime failures in general follow what's popularly referred to as the "bathtub curve". Where failure rates are high initially as manufacturing defects are exposed, then there is a long period of low incidence as the product functions as designed, and then at the end of useful life, the failure rate increases again as parts wear out.

It is safe to say, though, that the modifications that LN is selling are stronger, more robust parts than the ones they are replacing and will most certainly have a positive effect on failure rate. The magnitude of the effect is what remains to be seen.

[ridetheworld]

I have spoken to two 986 owners and one 996 owner since I have had my Box S (September 09). None of them knew what the IMS was or had ever heard of a failure. Admittedly they were older guys that didn't look to be very interested in forums. One of them had an RMS leak at one point and they updated him to the new seal when he had his clutch replaced. The other issues they had were catalytic converters (one 986) and a problem with the flywheel but nothing with the engines. They all had 50+k on their cars.

[mikefocke]

And I believe I tried to make the same point ... that we had lots of units tested, just not enough cars with enough miles on them to be really really significant in how the fix would hold up over time. And if the failure rate was 1-2% or 10-20% as some have said and occurs most often after 20-40k miles as others have said (and I have no freaking idea what of those stats are true or how accurate they are but they seem reasonable) then lots of miles on even a relatively few cars gets to be important in understanding how the new and improved part stands up to the variety of conditions a car experiences over its life.

Do I think the IMS bearing design from Charles is probably much better than the originals it replaces? Yes but that is based on theory and limited tests so far. This time next year my confidence curve should start accelerating upwards.

(But if I started to have a problem, would I put in a Porsche IMS or an LN IMS bearing? That one is really really easy to answer. Better the still partially unproven than the proven in this case . And if I win the lottery, Jake would get my car for a total upgrade the next week.)

[MikenOH]

Originally Posted by mikefocke

I said early on in public (and privately to Jake) I'd need to watch and see the number of cars done and their mileage before I'd be able to tell the success of the program. And I said this while pointing people to look at the Charles/Jake products/programs so you know I'm not anti..just skeptical as I feel we all should be of any maker/supplier's claims.

I was once responsible for producing a complex product and I know that testing a large number of units can reveal parts quality variation problems. And length of use testing/monitoring can revel suitability issues...in the case of cars, suitability over a wide range of conditions from 2 mile Walmart runs to racing, from Alaska cold to Death Valley heat, from every 3 months (!) oil changes to every year.

Lets use those numbers cited in the quote below and assume he has been doing these for ~10 months. 15 done. Average 1.5 per month. 82.5 estimated months of use. 2k miles per month. Translates to maybe 165k miles of testing. Pretty darn good. Especially considering that there are another 85 out there of some approximately similar longevity done somewhere else by someone else.

Consider that the IMS failures are normally at the 20k-60k miles point according to the way I read the stories and don't occur in all the factory units. We haven't achieved enough cars with IMS mods getting well through that mileage. We have more than enough units tested. But not in miles per unit tested. Once that number gets much higher than it now is, I think we'll be able to say for certain that the replacement design is better than the original. Until that time, the theory sounds good (and I'd go that route if I needed to) but my intellectual jury is still out.

This gets even more complicated because every car is different in the number of mods that get done to it and the individual mods change over time. So there are many combinations...many one of a kind.

And is the success truly perfect? We haven't heard of a single product failure, have we? (IIRC there was an engine that failed but it was not one of their products that failed) Is that normal?

And as for value added in the resale market by these improvements, I somehow doubt they will bring back much of their cost considering almost no other mods do. I've seen people say you get 10-15% back on the cost of your mods if you are lucky and sometimes the mods make it harder to sell the car.

Suppose the average potential buyer sees 2 cars advertised:
car 1: complete history, no major problems and no unresolved problems
car 2: major internal engine improvements to improve reliability

Is car 2's advertising confidence building or doubt creating? I know when I was looking for a Porsche, I originally thought of the 928 but the number advertised with very extensive rework told me this would not be an easy/cheap car to keep for a long time. So which car will the average buyer pay more for? Be looking at first?

I certainly wish the original thread poster good experience with his mods. And hope this discussion hasn't thrown too much cold water on his increased enjoyment and confidence in the reliability of his engine. I certainly think he did the mods at the right time when the clutch needed to be done too so the total expense was minimized. And he got a nice trip out of it.


Trust but verify.

I agree with what you're saying Mike but because few of these cars are used as daily drivers and annual mileage is probably closer to 8K/year than the typical 12-15K that a daily driver might get, it will take years to get to that 20-60K mileage with Raby's mods in sufficient numbers to demonstrate with certainty that his solutions stop the ticking time bomb in these motors .

In the mean time, owners, especially of the 2001-2004 models with 20K+ on them, have an interesting decision to make. Continue to drive the car and change to the oil at more frequent intervals than Porsche recommends and hope the motor doesn't grenade, sell the car or try to do something preemptive--like Jake's fix.

Since we don't know why all of these bearings don't fail in the first 50K, there is no way you can know with any degree of certainty which end of the equation a Boxster owner of these years might end up.
But what we do know, from jake's work, is that there are multiple flaws in the design/materials selection of the engine, any of which can take the motor out. We also know that Porsche--for their own reasons-- heightened the problem by going with a single race bearing and substituting plastic for metal on the tensioner pad (based on Jake's and others assessments).

Individuals will make their own decisions, but if I had one of those years, I'd bite the bullet and spend the $3k+ to make the changes or bail.

One other thought--I wonder if Jake would consider a preemptive exam on a car with over 100k on it to inspect by boroscope or other means to look at the IMS and tensioner assy; Marc W's 2002 MY car comes to mind. There is a reason why that car has not failed to this point. I think it would be instructive to know what's going on inside that engine.

[mikefocke]

Is we'd get to read about MarcW's 4k+ trip to Cleveland GA and back..he always manages to have an adventure.

I don't disagree with your "the owners face choices" discussion. Heck, with 56k on my '01, I do too. I guess I'm just a risk taker in that I turned down a 3 year extended warranty when I bought 4 years ago and made out. And I'm situated that, if I wanted to get a engine after this one failed, I could. Plus I have multiple vehicles and little real need for any one. Thus I have a different risk profile than many.

I just don't want people to think that this fix is the perfect solution until it is proven. After all, Porsche changed the design several times thinking that each change was the final perfect solution..and none of them were. So there is still a chance that this one isn't either.

And there are probably a couple of dozen other failure points so, even if the IMS is perfect, the engine can still fail. How many fixes and which ones will statistically make economic sense to be applied to the engine?

For example, we don't know how thousands of dry starts (after 2 days of not starting the car the oil has drained away from the IMS bearing which is now oiled by the crankcase oil (and not by the grease of the original)) will wear. Or how Minnesota winters or Arizona summers..or 3 months of storage...or many of the other varying conditions will have an effect on the bearing.

So if anyone else wants to spend the $ as a preventative measure against something that may or may not happen, I'm not criticizing them..rather thanking them for increasing the testing sample size.

I'm just saying the statistical probability of that being the right decision isn't as obvious to me yet as some are making it out to be.

[MikenOH]

Yeah, I figure if he puts crash bars on the front of the Boxster and scented it with the stuff that keeps deer away, he'd have a good chance of getting there in one piece without the help of a flatbed truck.

[mikefocke]

Volvo repellent too!!!

[yimmy149]

I wish there was "catastrophic" insurance for cars like there is for health insurance, something that would only kick in if the engine cratered (and had been properly maintained). I can afford to replace a $3k part... But a whole new engine. Then again, most other cars, the engine is a $3k part.

-james

[Paul]

Is their anyone here that drives their car year round and more than 9500 miles a year that has experienced an IMS failure?