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Old 05-29-2009, 04:08 PM   #69 (permalink)
Phimosis
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Quote:
Originally Posted by Josh@STILLEN View Post
The factory pulley is NOT balanced, and the dampening employed on the pulley is to protect the engine from the outside influences going inward.
Something is fishy here. The picture of the crank pulley that Wstar and the picture of the crank pulley that Josh at Stillen posted both have holes drilled on the back side of the inertia ring of the damper, but the holes are at different positions. This indicates the pulley IS balanced. It is a common technique to spin the object, then drill holes to remove metal, drilling the holes deeper to remove more metal as needed, to balance the rotating object.

For a better explanation of whether this is, or is not a damper, read the article by Steve Dinan, of Dinan racing:

http://www.dinancars.com/bmw/technia...armonic-damper


Also, the response from Stillen didn't adress my primary arguement, that if the pulley needs to be damped to prevent the pulley from damaging the engine, then every other pulley needs to be damped to prevent damage to the water pump, alternator, AC pump and power steering pump, but they are also cast units that do not have rubber dampers. I swear you guys rationalized your logic after you built the part. Show me some evidence that your argument is correct. Maybe some whitepapers from Nissan?

Last edited by Phimosis; 05-29-2009 at 04:56 PM.
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