Suspicious looking IWISS timing chain delivered today...

[85RedCarrera]

I received two new IWIS timing chains (not from our host), and when I opened the boxes, here is what I found: the rollers all have seams in them, and they also have more side-to-side play than my old chains.

Is this really how the IWIS chains are made? My original chains do not have seams in the rollers. I wouldn't put these chains on my bicycle!
Part # 99310552900





Here is my original chain:

[porschedude996]

Originally Posted by 85RedCarrera

I received two new IWISS timing chains (not from our host), and when I opened the boxes, here is what I found: the rollers all have seams in them, and they also have more side-to-side play than my old chains.

Is this really how the IWISS chains are made? My original chains do not have seams in the rollers. I wouldn't put these chains on my bicycle!
Part # 99310552900





Here is my original chain:

I’ve never seen that. I wouldn’t use them.

[silverlock]

What’s the batch number / any other details from the packaging that might be suspect?

[85RedCarrera]

Originally Posted by silverlock

What’s the batch number / any other details from the packaging that might be suspect?

I’ve never purchased timing chains for a 911 before, so I’m not sure whether anything looks unusual with the packaging & labeling. I am sending them back today, but am wondering which chains I should order to avoid this from happening again?

[gled49]

I don’t know about anyone else but chains have had the seam for a long time, back to the 90’s if I’m not mistaken.

[walt]

Appears to be made from rolled sheet now. Iwiss is a quality vendor and I'd hold off on sending them back without further research. You may get more of the same from someone else.

[85RedCarrera]

Originally Posted by gled49

I don’t know about anyone else but chains have had the seam for a long time, back to the 90’s if I’m not mistaken.

That is exactly what I’m trying to find out- the chains I removed from my 3.2 do not have any seams in the rollers, and I would like to replace with the same. I could be wrong, but I would expect seams in the rollers to accelerate sprocket wear?

Hopefully an expert will weight in on this one.

[Flat6pac]

I don’t believe there is any experts
The posting made me look at the parts for the current build, same thing.
Why after 60 years producing a supply, supplier finds a need for change quality as we
see pricing increase by 50%.
Bruce

[Dpmulvan]

Could be counterfeit, boxes I have note the holographic seal. These are old stock from the 90’s.

[al lkosmal]

IWIS has two configurations....IWIS and IWIS Racing. The IWIS Racing version is listed as higher strength for racing and sports purposes.....i just so happen to have a set of the racing versions on my shelf and the label specifically states that they are the IWIS Racing versions and......no seams.....You might want to check with your supplier to verify that is the difference between what you have received and the racing version....Here is a pic of the IWIS Racing label

[85RedCarrera]

Originally Posted by al lkosmal

IWIS has two configurations....IWIS and IWIS Racing. The IWIS Racing version is listed as higher strength for racing and sports purposes.....i just so happen to have a set of the racing versions on my shelf and the label specifically states that they are the IWIS Racing versions and......no seams.....You might want to check with your supplier to verify that is the difference between what you have received and the racing version....Here is a pic of the IWIS Racing label

That is interesting... so the factory used a roller without a seam, and the standard replacement now has a seam? Even the chains from Por$che?

I had chosen not to order the race chains, as I have been told that they are sealed rollers, and to me that means that there is the potential for reduced longevity. Great for a track car, but I would prefer to have the rollers benefit from the oil bath they will be running in...and last as long as the last set of chains lasted.

For the life of me, I cannot understand why anyone would want chain rollers with seams in them. I guess I've got more research to do on this.

[rwest]

You might want to post this in the engine rebuilding section to see what rebuilders are using?

[ian c2]

Off topic , but I’m the middle of an untimely unwanted project on my daily .
This thread had me looking at the timing chains I’m replacing on the replacement engine before it goes in (a mixture of scope-creep and warm&fuzzies whilst careening hopelessly down a well lubricated slope)
The new and old chains have the same seamed roller , but also have what appears to be an oiling hole ?
I’ve not checked the idler sprocket nor done any measurements yet , but suspect plastic guide wearing and limited self-adjustment of tensioners is the main factor to “stretched chain” reports .
( 4 cylinder 2.0 turbo diesel with @320 ft-lb at 1750 rpm )

NEW :



OLD (60k miles ;

[85RedCarrera]

The stickers on my boxes aren’t holographic, but they may have done away with those? I posted a link to this thread in the 911 engine building forum.

That pick of the rollers on your daily makes me shudder. I guess it’s been far too long since I opened up an engine with timing chains- I’ve never seen rollers formed this way.

[stownsen914]

I'm assembling an engine with the IWIS racing version. No seams or holes.

[PeteKz]

Dave, I haven't seen seamed rollers on chains before either, on cars or motorcycles.

Please do this: lay out or hold the chains so that you can compare the lengths of your old chains to the new ones. Are they the same length? If so, I would judge the old chains are not worn and I would reuse those instead.

[4sd911]

I noticed this in a 2010 rebuild. The new chains rollers have the seam like you show, my old chains are seam less.

[2jmotorsports]

I would contact the supplier with your concern and photos. A while back I did the same with some GT3 main & rod bearings I had questions on and they were willing to double check their stock and even show me paperwork from their supplier (Porsche itself).

Many times manufacturers roll out changes without letting the rest of the supply chain know.

[85RedCarrera]

Thanks guys. I measured my old chains and they are about 0.5mm longer total length than the new ones (0.25mm longer when hanging on a pegboard rod). Since my odometer broke at 215k and there is no evidence that anyone ever replaced the chains, I am a bit reluctant to re-use my old ones, even though I would bet that they would be fine. I had a soft tensioner and some chain flapping when I bought it, and have no idea how long that was going on for prior to my ownership, so I think I will be more comfortable finding a solid roller replacement. The IWIS racing chains apparently are solid roller, but I have heard that they are sealed rollers, and so those would not be my first choice. I am sending these back to AH for now.

[PeteKz]

Dave thanks for measuring the lengths. With 215Kmi, a stretch of only .25mm when hanging (.5mm over the length) verifies what I've seen, which is that the cam chains wear very little.