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Old 12-23-2016, 01:13 AM
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Justin Tyme
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Default Head studs

Chaps,

Ripping down the 4.7 litre engine. There's a possibility it might get some modest boost in the future (more on that later), although could stay NA.

Do I need to replace the head studs ?

If so, what does a set cost (roughly) ? I need 18 x long and 2 x short, right ?

Thanks !!!
Old 12-23-2016, 02:16 AM
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Daniel5691
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Hello !!!!!

bon appetit !
https://rennlist.com/forums/928-foru...ead-studs.html

p.s. I did decide to replace mine, and plan to follow the modified tightening procedure described in the last few (most recent) posts of the thread above.... good luck, please post your thoughts/decision if convenient...

cheers
Old 12-23-2016, 04:48 AM
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Justin Tyme
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I know, and the thread is a nightmare.

I'm looking at Porsche OEM studs. So WTF ??? Do I just torque them down to whatever ft/lb ? Or do some 90 degree thing ?

It's confusing..
Old 12-23-2016, 06:27 AM
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The Forgotten On
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If they are original, do Porsche's specified angle torquing method. If they are new, torque them to 66 ft/lbs.

Porsche changed the alloy in the studs and they don't stretch as much anymore, so following the angle torquing method with the new studs will result in a torque spec of over 100 ft/lbs. No bueno.

That is the gist of it from the technical (nightmare) thread on this.
Old 12-23-2016, 06:32 AM
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Justin Tyme
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Cool..thanks !

They are new (well, they will be once I buy them) .... Porsche OEM from Germany. So they get torqued to 66ft/lbs.

How easy was that ?
Old 12-23-2016, 12:18 PM
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GregBBRD
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Originally Posted by Justin Tyme
Chaps,

Ripping down the 4.7 litre engine. There's a possibility it might get some modest boost in the future (more on that later), although could stay NA.

Do I need to replace the head studs ?

If so, what does a set cost (roughly) ? I need 18 x long and 2 x short, right ?

Thanks !!!
If they are not corroded, leave them alone.

If one is corroded, you need to replace all.
Old 12-23-2016, 09:03 PM
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Justin Tyme
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Thanks Greg, sage advice !
Old 12-25-2016, 05:08 AM
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Roy928tt
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I run up to 15 psi of boost in my 4.5, head gaskets have been replaced, studs were not replaced, all is good....
Old 12-25-2016, 05:32 AM
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Justin Tyme
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Nice....pm sent !



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