996 3.4 IMSB "spacers" question

So, I bought a 2001 C4 back in February with good records, but no record of an IMSB change. That, added with the fact that the car has 129k miles and getting weird cam deviation figures, I figured I'd drop the engine to do VarioCam chain guides and the IMSB, along with all the "while you're in there" things. Engine is out, after locking the crank, cams, and removing chain tensioners, I was pleasantly greeted by what seems to be a old dual row LN bearing, in fantastic shape. I have record of a RMS being replaced 90k miles ago, so I assume that's when this was done. LN has no record of the install. I ordered the pelican parts kit, and now have a question on what array of spacers to use. So, I know I use the outer race spacer since my car had a dual row. Now, do I use the inner race spacer on the flange shaft, or do I just install the new single row as is on my flange, and use the small spacer on the front so that the threads on the center stud are usable? Where does the small black o ring go? Without the inner race spacer, the beveled end of the flange mates nicely up to the bottom of the center shaft, with the o ring down there. With the inner race spacer in place, it doesn't. Pictures following, as I imagine this would be hard to answer without them. I think the correct answer is Bearing, outer race spacer, spiroloc, flange with inner race spacer and new seal, done, but I'd like some confirmation before I start buttoning things up. Thanks! This is how I currently have it installed, but obviously with the outer race spacer on the front of the bearing. This is with just the inner race spacer, which can be seen here. What was removed from my car. An older LN setup.

I've never seen anything like this. Spacers on an IMSB? Dual row to a single row? I think you are making a big mistake. It looks like the Pelican Parts "kit" is garbage, and if you can't get instructions from them about installation, well, there ya go. I say pony up for the LN IMSB Solution and be done with it...forever. In for a penny, in for a pound.

I'm pretty sure lots of people have used this kit successfully. It's a quality bearing that should last 40-50k miles. I believe even LN says the IMS solution is good for "5 years/unlimited mileage". I would rather just put a new quality bearing in at set intervals via a drastically cheaper option. If this was some eBay kit from China with no known users, i would run the other direction, but its a quality NSK Japan bearing. I think i found the issue, still would like some confirmation if possible. The LN flange is made for LN's dual row, which is slightly thinner to make use of the spiroloc. So, the shaft of the LN flange has a deeper mating surface than a factory Porsche dual row flange, but not as deep as a factory Porsche single row flange. In short, i think i need a new factory Porsche dual row flange in order to properly use this setup.

I would agree it isn't clear what you are trying to do. What exactly did you buy from Pelican? You mentioned you were replacing the IMSB but your questions are on the flange. Did you replace the bearing? Whatever bearing replacement you used should have had the flange accessories to go with that?

You must have been replying as I was typing. Looking at pelicans site and the issue you are describing, I assume you must have bought the $189 bearing kit that "replaces either single row or duo row bearing" ? And know you are trying to make it work with a flange built for another bearing type. I'm guessing you are right that the LN flange won't work. I don't see that they even list who makes that bearing so I'm not sure you will find help here with mix matching stuff together. I know you have already expressed your confidence in this bearing, so i would agree contact the people who made this bearing to understand what to do.. Good luck.

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Correct. I just ordered a factory dual row flange, should be here tomorrow. We will see. Pelican told me their kit is designed to work with the factory flange, and that they are unsure if it would work with the LN flange, which i think we've solved here, it won't. I was unaware, until today, that LN's flange is different than both the factory Porsche flanges in order to accommodate their bearing

Wow...

If you already have the LN flange, why not just order the replacement bearing? Or is that not available without the whole kit? Mine has the Solution now but its a thing I hadn't considered..

Be aware that I had a replacement bearing fail (not Pelican, most likely FVD Brombacher) in my car. Most likely, if I had kept the stock bearing, the engine would still be fine. So don't assume that every third-party bearing is a good replacement! I myself would never install anything except LN Solution or Retrofit.

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I would give LN Engineering a call. They can walk you thru what to buy and do. Why mix oranges with apples at this stage. Whether it's the retro or the solution, both are outstanding products. The one you choose will depend on your objectives for your car and service levels you will employ going forward.

This is a terrible idea. Why delete the advantage of having a dual row bearing? In your case, I would have left the replaced dual row in there instead of installing this single row kit.

Well, I installed the bearing with the new flange, it fit perfectly. Just finished replacing cam guides on bank 1, on to bank 2 now, should be finished today. Engine is remarkably clean for 130k miles. Chain guides were shot! Glad I caught them before they broke

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Good job. Did you replace the small chains? I did this job three years ago but did not replace them. Thinking of going back in this winter while the engine is out.