Rauch & Spiegel Cam Sprockets?

[85RedCarrera]

As I continue to slowly assemble the parts for my 3.2 to 3.4 build, I still have unresolved questions hanging out there that I was hoping some of you might be willing to speak on-

1. Do I use the IMS and cam sprockets from my old unknown mileage engine (they show little apparent wear- but this is my first Porsche build- I am experienced regarding evaluating motorcycle primary drive chains/sprockets, so I understand what to look for there in regards to sprocket wear…but I am less familiar with the typical 911 timing gear wear patterns), or should I consider the R&S sprockets that L&N offers? I called them and the guy on the phone couldn’t tell me anything about the sprockets or how they might be different from the current OEM sprockets offered…. I have read enough in this forum, and spoken to a couple of builders, to know that buying the OEM sprockets is the least desirable choice.

2. Do I buy the latest IWIS standard replacement timing chains that now have seams in the rollers, or do I buy the IWIS “race” chains that are apparently sealed chains that have been pre-stretched? I am building the engine for street use, and will not track the car- so I am building the engine primarily for reliability/longevity.

[EDIT] I fixed some crazy typos in this post.

Any input appreciated,

Dave

[draw]

I went through a similar thought process as you and did some testing starting in post #85 of my build thread. The short answer is that there is a difference between the R&S sprockets and the others...

Originally Posted by draw

Before doing that, I ordered two sprockets made by Rauch & Spiegel that claim that they "are the good ones, made in Germany for us from the proper material with the proper heat treatment." However, I was skeptical of this claim.

Rauch & Spiegel on the left, new genuine Porsche on the right...



I didn't get a "real" scratch on the Rauch & Spiegel sprocket until I used the HRC65 file. The original part came in at less than HRC40. I think this confirms their claim that they are properly heat treated.



This settles it for me. I'm going to use the Rauch & Spiegel sprockets.

[85RedCarrera]

Originally Posted by draw

I went through a similar thought process as you and did some testing starting in post #85 of my build thread. The short answer is that there is a difference between the R&S sprockets and the others...

Now that there is some really useful information.

Thank you, draw!