Who has done an IMS change (New Oil Fed Design Idea)

[Cajundaddy]

Thanks Tim for walking us through your fact finding and R&D project. I think your positive oiling method has great promise. Keeping everything floating on a film of oil eliminates a bunch of wear and heat issues. I agree with Brando that your external oil tubing may be too exposed for the rigors of track use or even a DD that periodically uses a gravel turnout. Anytime a car goes off track/off road the underside takes a good pounding by rocks and gravel being kicked up at high speed. Routing from an internal oil galley would give your design better survivability under those conditions. Keep the updates coming. This is the stuff Porsche should have been doing 10 years ago. FYI: That blue/green oil reminds me of Torco oil we used in motorcycle racing years ago.

[feelyx]

Thanks for the comments Cajundaddy.... Yes, I already have the oil line made up and ready to test. I had to figure a way to drill it without dropping metal into the oil galley, which I've successfully done, but have to test more holes.

The tubing is tougher than it looks, its not your normal teflon tubing. I couldn't break the connection or tubing swinging a hammer on my test case. I did however mess up a filter housing.

[feelyx]

Ok here's the drill vac that will be needed to drill the oil galley. Very simple.....




Here is a video of it in action, sorry for the shaky/blurries, I was trying to video while drilling..... well anyways....
I have been testing it on all the cavities on the test case and it never drops a speck of metal. Hooks right to the shop vac. It also works with a tap when threading the hole.




Onward...

[Brando]

Status update?

Were you able to tap the galley without any incident?

[feelyx]

Originally Posted by Brando

Status update?

Were you able to tap the galley without any incident?

Hi Brando Yes I was able to do it without incident, the last video although not very good shows the drilling of the block. I made swiss cheese out of places to make sure the drilling and tapping did not leave a single spec of metal behind.
The car is running great, I have had no problems with it, the durametric shows straight line cam deviation, No leaks, or pressure problems, etc. Although, I might set the volume to 1/4 qt per minute instead of the 1/2 qt per minute I have now, as it doesn't need that much oil flow.
I take it out 1 or 2 times a day to stretch the legs Realistically...... my main concern with anything on this car anymore is.... if I get a flat tire

[turboflyer]

Originally Posted by feelyx

Ok here's the drill vac that will be needed to drill the oil galley. Very simple.....




Here is a video of it in action, sorry for the shaky/blurries, I was trying to video while drilling..... well anyways....
I have been testing it on all the cavities on the test case and it never drops a speck of metal. Hooks right to the shop vac. It also works with a tap when threading the hole.




Onward...

Amazing thread and you are modest. What an innovator. Don't suppose you would know where to tap the differential with that vac drill for a drain would you?

[feelyx]

Originally Posted by turboflyer

Amazing thread and you are modest. What an innovator. Don't suppose you would know where to tap the differential with that vac drill for a drain would you?

Hi turboflyer .... Thanks! I'm sorry but I have not seen the inside of the differential, so I could not say. I will say the drill vac would be perfect for that

[feelyx]

Still running awesome......

I was working on the sump/cooler project today and had a bilge booster fan I was playing with to stuff a mock up of my cooler into

I wired and tied the fan vertically in the engine bay with the exhaust pointing down to see if the noise level, or running the fan would cause any disturbance with driving.
What I found out is, it lowered the temps in the engine compartment significantly, the engine temps were the same, but the compartment was cooling down. After spirited drives with and without it on. 12F was an average drop in temps in the engine bay.
More defined testing will be needed though.
Here is the start of the cooler mock up, there is 10ft of tubing in there.


Onward.....

[feelyx]

Update..... Running great, pulled the filter, put it under the microscope. No heavy metals found in the search.
Pricing..... (As this to date) with removing the oiler from the filter and putting a line from the gallley, also with the removal of the $14 O ring to a normal o ring. Since the bearing cover has a lip that is flush with the case, and the interference fit of the cover the $14 seal won't be necessary. Use 5900 around the edge if sealant is necessary. So now price is down to $182 standard bearing and $210 ceramic.
edit: 2590 mi. On bearing and filter. And a japan bearing I found will drop the price more if it passes inspection
Onward.........

[mikefocke]

So you feel comfortable selling a set of parts that have been tested on one engine for perhaps 3-4k miles? Recall that Porsche had all of their test mules and still got it wrong but I'd feel a lot better if there were some long term results and multiple engine testing before the consumer has to be the test case.

Your offering a choice of bearings also tells me that individual testing should be done on each bearing and involve both rev 1 and rev 2 bearing replacements.

This is the same concern I raised with Casper, LN, Pelican. That and instructions, installation tools, support hotline, etc. As one who used to produce a product, in my world development was less than a third of the cost/time.

[feelyx]

Hi Mike, Thanks for the comments. Actually this is not for sale. At this point I am not sure if it will be for sale or not. That will be up to the mfg of the product.
Also I am not the only one testing this but not privy to the testing. I can only post what I am doing.
Hope this helps your concerns...

[feelyx]

Update still running like a champ.... even in stop and go traffic, freeway runs... curvy back road and mountain runs, idling for long periods. I guess the next step is to run it on a track and also some autocross sessions with it

The oilcooler is almost done, just a few more changes to the exhaust cone to get the most out of the air movement.

Onward....

[harrisracing]

Feelyx,

First of all, kudos on what is an incredible amount of R&D work! I can't believe Porsche hasn't contacted you to pay you off from publishing your findings on this yet! Seems like a class action attorney would be calling you as an expert witness here.

As a mechanical engineer and fellow car enthusiast / hobbyist, I really have enjoyed the thoroughness of this thread. My IMMEDIATE thought about the IMS failures from my first reading about them is "Why in the heck did Porsche send a minimally lubed ball bearing to do a pressure-fed journal bearing's job?". I mean Porsche crankshafts have been handling ludicrous loads through split cases for years without using ball bearings! Now I see that you didn't go all the way to straight "journal" bearing, but all of your theories and logic to support oil flushed bearings to extend life have been very sound up to this point.

I wonder what making adapters to utilize an existing (or commercially available) camshaft bearing of some sort and putting your oil feed on them would do to your costs and bearing life (Afterall we are really just looking at camshaft speeds of rotation and loads here)?

I do have another question / comment about the oil galley drilling: Is this an "exit" oil galley? For example, after I drill the hole, can I then just force oil through the oil filter housing somehow to push oil back out of the freshly-drilled hole and flush it (as opposed to your drill/vac device? Just curious to see if there is a simpler way to flush that. (sorry if this doesn't apply, but I can't watch the videos from this computer).

Having "acquired" a car with a recent IMS failure, I will DEFINITELY be looking at my IMS replacement options from this point on.

Thank You and good luck in the conclusion of this long-winded perplexing problem
Patrick

[feelyx]

Hi Patrick.... Thanks for the comments, Here are some pics where the oil galley leads to... up to the oil cooler. In all praticality you just need an aluminium plate with a fitting on the cool side between the cooler and block to have an exterior oil galley leading to the bearing. But, to answer the question, yes, you can remove the cooler and flush it down to the filter area with the filter housing off. Sorta back flush...









Ummm.... more on the cam stuff later.....

[harrisracing]

I witnessed a high speed, high torque gearbox Factory Acceptance Test (FAT). After asking why almost ALL of their gearboxes use journal bearings instead of ball bearings he stated that the ball bearings simply just don't last because ball bearings rely on a very small contact area to carry a whole bunch of load (balls on races), this isn't a good scenario for trash, which in a ball bearing will almost surely get crushed into the race where a journal bearing could pass right through the film level.

The front of the IMS doesn't wear out does it? Is it an oil-fed journal bearing or just a wetted bushing? No ball bearings there, right?

I have also pulled out my book on journal bearing design and will let you know what I find there as well.

I'd surely like to see a good ole fashioned "journal bearing" replace years of Porsche engineer's failures...but there HAS to be a reason they picked the ball bearings time and time again...?

Patrick

[feelyx]

Hi Patrick...
The front "bushing" IIRC is oil fed from the pump, there is actually no bushing there it is hard faced aluminum to prevent excessive wear, and is over 25mm long.
I actually tried to use a bushing at first as I thought that would cure the problem. But through trial and error, I found that chain pull in that area was too great and would wear a groove into the bushing in a short period of time. I went as wide as 40mm on the journal, trying to remove the grooving, but it just made a wider groove.
What I "think" was doing it in... was there isn't enough room for any depth to the bushing. Max depth available was 12mm for a bushing, anything longer and it started using it as a lever on the IMS cover.
Right now I am working out the details with a company using the cover itself as the bearing, so when they forge the cover, it includes the outer race. Then after machining, the bearing is assembled in the cover as 1 pc. So basically you have a bearing with an outer flange that bolts into place. It also provides for a bigger bearing in the confined area.

[harrisracing]

feelyx,

Ahh...makes sense that you tried a true bushing there and it makes more sense that this wouldn't work if it only had 1/2" or so of length to the shaft at the journal area. What clearances were you using for the shaft? What materials and temperature ranges for expansion did you expect? I am still curious if there is a way to do it and get the 25mm or so that I think you would need.

I dusted off my machine design book and brushed up on the entire section of Journal bearing design. If you would be so kind as to post a sketch of the depths and diameters of the IMS shaft and it's relation to the case flange (and case flange ID) I can start working on a solution for a pressure fed journal bearing in this location.

What my initial thoughts (depending on how far you can go inside the IMS shaft) are to machine a solid rod that can be frozen and shrunk fit inside the IMS shaft where the existing bearing is circlipped inside. This rod will be burnished on the outside and will basically act as an extension of the shaft and a long bearing surface for our journal bearing to ride. You are correct I think again on making the external race as large as possible here, but in journal bearings the: length, clearance, and pressure are everything (because temperatures and oil viscosity are already decided within this engine).

Now I understand getting this shrunk-fit shaft extension to be concentric would be a serious challenge indeed, so I really don't think that would be an ultimate solution for a "regular fix"
as I believe the shaft would have to be removed to do any type of service like this...but conveniently my motor will be coming apart soon.

To make the shaft extension PERFECT, the shaft would have to be removed, this material added to it (shrink fit or other), then turned and trued on a lathe to make sure the "extension" would be concentric with the existing shaft...but if there is enough depth to it, we "may" be able to get away with shrink-fitting a pin inside it. The rest is easy, find a circular bearing and make an adapter at the IMS flange to fit this bearing within it, figure oil supply and check for wear periodically.

I have ALL of the math to get the journal width and oil supply figured out right in front of me now. I can at the least put the numbers on paper in theory to see if it would fly.

I do, however, understand what you are saying about the IMS rotation point being too far away from the IMS flange in the case making too much of a lever arm for the proper support. With my method of lengthening the IMS shaft almost outside of the case, I think proper support is possible.

Just trying to mix your already "out of the box" thinking with my "way out in left field" thinking. Either way, we both agree that the Porsche method was an engineering mistake.

Patrick

[harrisracing]

I am seeing what you are saying now from your picture on page 10 of the "sprocket cluster" being SO close to the case and the IMS flange. That being said...

Looks like the only room you have for a journal of any length happens INSIDE the IMS sprocket where the circlip is...which puts too much moment on the IMS flange outside the case. AND if you try to extend the shaft outward you run out of space between new extension and the flywheel interference area of the flange. That would prove to be problematic for sure - UNLESS you had the shaft out already as I previously stated. Then you could cut back the sprocket (10mm or so), which would give you clearance to likely increase your bushing length by up to 20mm if you add the extension that I am talking about.

Just trying to help.

Thanks again,

Patrick

[harrisracing]

This is a quick sketch (NOT TO SCALE) I came up with regarding the existing IMS bearing layout with relation to the end of the case, etc.

Could you please get me some dimensions on this?

Also, What about driving a cam bearing into the sprocket cluster of the IMS and making a more solid IMS flange? It should make for a stronger layout with less chance for catostrophic failure and still be able to be installed from outside and easily serviced. I am sketching this as well.

Thank You,
Patrick

[feelyx]

Patrick, The best I can tell you is open up a motor and see whats all the buzz is about. I could tell you something and you could interpret as another. Another thing to do is purchase an IMS shaft and cut it in half. Yes minimal clearances in the whole area in there. I'm always available for questons (quality guess work at a reasonable price.. ).
I am almost done with the mods to the final product, and will be starting the oil sump/cooler part soon as I want to drop my oil temps from 215F to under 190F.