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Re: was Re: Weepy Head Gskt Fix!is stretch bolt defence clamping methods,

Excellent post, thanks...

At 03:19 PM 12/28/97 -0600, you wrote:
>-----Original Message-----
>From: Avi <Avi@cosmoslink.net>
>To: Mik Tip
>Cc: quattro@coimbra.ans.net
>Date: Sunday, December 28, 1997 12:24 PM
>Subject: Re: was Re: Weepy Head Gskt Fix!is stretch bolt defence clamping
>>My last comment(last question)is: if you are not using the studs "as studs"
>>meaning a natural alignment, why not use bolts (raceware, if you
>Personally, I have no problems with the OEM bolts, on a "stock" motor!
>I have, however, seen the OEM's allow head gasket problems from loosening!
>I have worked on engines(VW & Audi)where the OEM bolts can be removed by
>Attributed to factors inherant to the stretch bolts, combined with the
>continual heating &
>cooling, along with the different rates of expansion and contraction between
>aluminum head and steel block!
>The Raceware's are a "very precision" machined component;  40% stronger than
>OEM.  190,000 psi tensile strength!  8740 Chromolly, J formed rolled threads
>MIL spec standard's, and black oxide coated. Granted most will never need
>that much, but
>some do, or Raceware wouldnt be in buisness! (No affiliation)
>One very important advantage of the "stud", is it doesnt "wind-up" like the
>bolt when tightning.
>This is important because the bolt has "stored energy" that causes it to
>unwind.  The "stud"
>maintains correct torque retention better than the bolt.
>Studs also provide a improved inherant design integrety with extra material
>since they arent "required" to stretch.  They're also very reusable!
>The "nut & washer" are also very precise, and provide for more accurite
>reading's for instillation.
>Of course all this comes with a price!   A set for an Audi 5 cylinder costs
>about $135.
>The engine I built a couple of years ago had over $2000 worth of rare parts,
>so the $135 was cheap insurance.
>>.....here is my version (of answer), bolts are much more costly to
>>make (in small quantity and from special material which i presume the
>>raceware hardware is), so it is "STUDS", i am also guessing (never saw
>>one), that the raceware hardware (threads) "is cut not rolled as the OEM
>>factory is?........
>The initial start of this thread focused on the "weeping head gasket".
>Largely, I believe, is caused from the OEM stretch bolts, loosening.
>Granted, this loosening may be very minute, and combined with a
>"squashed" head gasket, take some years and mileage to develop.
>The only way to correctly "fix" the weeping gasket, is to change it!
>Installing the OEM bolts "may" allow the same problem to re-occur
>later on in the engines life.   But most folk's dont keep a car that long!
>The Raceware's are an "improved alternative" to the OEMS, but at
>a price!
>Mainly recommended as a "performance" type option for those
>seeking more "reliable" fastening of vital components, especially
>on "modified" engines.
>                                                            Mik