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BoxxerSix BoxxerSix is offline
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Join Date: Jun 2006
Location: Ballston Spa, NY
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Originally Posted by NathanUK View Post
The running in is for the seals, not just the bearings.

Only for the old carbon (positive seal that actually touches shaft) seals used for older draw through carburated setups where gasoline actually contacts the seal surface. Positive seal need breaking or they can deteriorate at the leading edge and/or crack due to excessive thrust loads before they reach their optimal broken in clearances.

New style dynamic seals are incorporated as a piston ring into the thrust washer(the part of the thrust bearing that floats on the turbine shaft AKA thrust ring) They break in very quickly.

Carbon Seal

Dynamic Seal

You will not find a carbon seal on a performance turbo these days unless it's been specifically built with it. Rajay and IHI are some companies that still use them to a degree Dynamic is a far more efficient seal, and durable for that matter.
Adam Hennessy
Old 10-03-2007, 05:59 PM
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