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Got Engine Vibrations??

 
Old 09-23-2017, 10:00 AM
  #16  
Bertrand Daoust
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Originally Posted by SeanR View Post
As Greg pointed out on FB, and I hadn't even thought it through that far. Once installed you don't have to take the hub off to do a belt job. The damper is a two piece system and the damper is easy to remove. Undo the 9 bolts holding it together and wammo, off.

The hub can be removed with relative ease with a decent hub puller, and you can get them at any local parts store or ebay.
Thanks for the precision Sean.

I also was wondering what we would do on a TB/WP job.

Looks like a great improvement part for our car.

Thanks to all involved.
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Old 09-23-2017, 10:34 AM
  #17  
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This is awesome. Thank you for posting about this dampener.
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Old 09-23-2017, 11:02 AM
  #18  
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Sean, thanks so much for the info. Now I'm ready to order. Hoi
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Old 09-23-2017, 12:30 PM
  #19  
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Originally Posted by SeanR View Post
It seemed to be all over the map. I could be cruising at 40 and feel it, not at 45, 120 and everything felt fine, get to 125 and it would happen. Cruising along was when it was most noticeable.
Thanks. I need to get into that 120-155 range more often to see how mine copes.
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Old 09-23-2017, 12:53 PM
  #20  
Daniel5691
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This is the damper that requires heating for install?
Could you describe the install process in detail?
Where to heat, etc, etc ?

Your time and knowledge are valuable commodities. Thank you very much for sharing both.
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Old 09-23-2017, 01:18 PM
  #21  
SeanR
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Greg sends some great instructions, even I could follow them.

Gist of it is to pull off old hub. Separate the hub and damper. Put damper in oven and heat to 240f. Clean up and oil crank snout. Put on gloves and pick up hot damper from oven then quickly get to the crank and slide the hub on all the way. Ok to use a rubber mallet to push it all the way (I didn't need to, it slid on quick and easy once I got the keyway lined up correctly)

Once hub is on let it cool then put the damper on the hub, blue loctite on bolts and toque down to the proper specs (provided).
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Old 09-23-2017, 02:25 PM
  #22  
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I have an engine pull upcoming for complete catch-up maintenance. Sounds like the additional labor would be fairly low once the engine is out/front of the engine is off. Sean (or Greg): I did not see this part on the Precision site. What's the availability and cost of this puppy? Thanks!

Charlie
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Old 09-23-2017, 02:26 PM
  #23  
SeanR
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Originally Posted by chart928s4 View Post
I have an engine pull upcoming for complete catch-up maintenance. Sounds like the additional labor would be fairly low once the engine is out/front of the engine is off. Sean (or Greg): I did not see this part on the Precision site. What's the availability and cost of this puppy? Thanks!

Charlie
I would call Mary (operations manager, Gregs wife and actual owner of the shop) on Monday and talk to her.
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Old 09-23-2017, 03:55 PM
  #24  
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Thank you, very informative thread ! ! !
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Old 10-05-2017, 03:49 PM
  #25  
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I changed the damper on my 86 900 turbo in 2005 and the motor became really quite and pleasant again. I can believe that this is a part with a finite life based on common sense and that experience.

So, here some interesting questions about this product:
1.) Are there different parts for the various engines (GT, OB, S4)? I believe the factory has different part numbers. This would make sense, because any damper needs to be tuned to the characteristic frequency of the system. Within limits, one could make the argument that any new damper is better than a 30 year old one. But, that is not really the answer I am looking for.
2.) Do any feedbacks exist about lifetime, etc.?

Since the 91GT is currently under the knife for the 30 year maintenance, I really would like to replace the harmonic damper now.
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Old 10-05-2017, 06:49 PM
  #26  
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Originally Posted by Red Flash View Post
I changed the damper on my 86 900 turbo in 2005 and the motor became really quite and pleasant again. I can believe that this is a part with a finite life based on common sense and that experience.

So, here some interesting questions about this product:
1.) Are there different parts for the various engines (GT, OB, S4)? I believe the factory has different part numbers. This would make sense, because any damper needs to be tuned to the characteristic frequency of the system. Within limits, one could make the argument that any new damper is better than a 30 year old one. But, that is not really the answer I am looking for.
2.) Do any feedbacks exist about lifetime, etc.?

Since the 91GT is currently under the knife for the 30 year maintenance, I really would like to replace the harmonic damper now.
Many of us just think the part numbers and different colors were to make the parts easy to identify on a shelf or identify an engine.

Greg Brown makes his damper the same for all 928 engines so I'm sure Porsche must have too since tuning for different engines is kind of a guessing game as all engines have their own individual idiosyncrasies.
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Old 10-05-2017, 07:02 PM
  #27  
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what is the cost?
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Old 10-05-2017, 07:06 PM
  #28  
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Something to remember is that the ATI Superdamper itself is an item that has been around for quite awhile. ATI, and more importantly, Greg Brown, have produced a center hub specific to the 928 crank shaft. The actual balancer itself is a relatively common ATI piece.

To my knowledge, it is spec'd out for a big block Chevrolet V-8. This ATI damper is a known, reputable quantity in the American V-8 engine world, as well as others, and has been for years.


http://www.atiracing.com/aboutati/aboutati.htm


http://www.atiracing.com/products/dampers/index.htm
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Old 10-05-2017, 08:34 PM
  #29  
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Originally Posted by SeanR View Post
I would call Mary (operations manager, Gregs wife and actual owner of the shop) on Monday and talk to her.
Sean, did you reply to "what did it feel like before"? I have a 'growwwl' at higher speeds/throttle settings that I cant chase down.
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Old 10-06-2017, 08:26 AM
  #30  
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Originally Posted by merchauser View Post
what is the cost?
Can someone please chime in on the cost? The website does not provide the price.
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