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Quote:
Originally Posted by Flieger View Post
I see that the Supertech design is very good but I still am in the differing thermal expansion rates camp. The Supertech steel is very strong I am sure but I do not think they have engineered the thermal expansion rate to more closely match Magnesium.
So Flieger as an engineer you must have calculated the actual expansion rate of the material involved in order to make your determination. So how much do they change?

What we a talking about is a temperature change of 100-120 degrees C randomly applied to multiple material including studs that are heated unevenly. Right?
So if the Dilivar studs change (grow) an appreciable amount (even under these small temperature range) and they are not heated evenly wouldn't that create an uneven clamping pressure on the heads?

All of this theory is an interesting exercise but most of it is just much to do about nothing. I prefer a static expansion that increases the head clamping pressure. Of course there is a limit but I have seen the Supertec studs in 800hp engines running nitrous and the heads didn't show signs of movement when disassembled for inspection. Dilivar studs show movement in NA street engines.
I have the Supertec studs in three of my engine builds (including a 450+hp turbo) and have never had an issue. Something I can't say about Dilivar.
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Old 12-14-2011, 08:00 AM
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