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Join Date: Oct 2005
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Originally Posted by WERK-I View Post
I think the debate on the ARP head studs revolved around the metallurgical characteristics of the studs. As you know these engines are modular in design and the thermal expansion rates are significant. Porsche spent a lot of time in designing studs that had close the same expansion rates as their corresponding counterparts. The debate around the ARP's was the studs losing their clamping force due to the heat cycling that takes place. This in turn, would require more diligence by the owners' part to routinely check torque settings on the heads. I don't know if I buy into that argument..... I'm no metallurgist.
That's my understanding of the "argument" as well. However, what's weird is that neither the Supertec nor the Performance Developments head studs (both often regarded as some of the best studs, even for turbo engines) come in the Dilivar material, so commonly known to have these expansion/contraction properties.
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Old 08-21-2008, 12:52 PM
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