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Gelbster · 08-23-2016, 08:11 AM

The ARP info is interesting as JFP asserts. I used it for all the many ARP bolts on my M96 rebuild.

Here is the ARP link - you'll see what I mean perhaps:
http://www.jegs.com/PDFs/ARPAssemblyLube.pdf
An example, if the manufacturer did the original spec based on the factory taped hole, he would have known exactly what the conditions in the hole were and wrote a spec accordingly -probably with dry thread resistance/friction in mind . On a used car, the threads may have been chased, badly re-cut,dirty,oily,have coolant ,grease,threadlock or whatever there. So how do you write a spec for that ? A competent mechanic (like JFP) uses experience and skill to find a reliable solution.The specifying engineer(if it was me) would decline to give a torque spec for the used car because I could never know what the friction was.Tell me the friction and the material and fastener type & size and yes, it is easy to give a torque range. With the M96 the limiting factor will usually be the ductility of the alloy of the block.
Geeks read more here:
http://www.designnotes.com/companion/manual-1.html

When I rebuilt my M96 I chased and cleaned all the threaded holes .In as many as possible I used custom length s/s studs in the engine(+red Loctite) and green for the s/s nuts. There will never be a problem there ! Corrosion is a risk that compels the use of some type of lubricant/sealant/locker regardless of the torque specs. The exhaust header bolts are a good example. Yes, mine are s/s !

08-23-2016, 08:11 AM	#75
Gelbster Registered User Join Date: May 2014 Location: S.California Posts: 2,029	The ARP info is interesting as JFP asserts. I used it for all the many ARP bolts on my M96 rebuild. Here is the ARP link - you'll see what I mean perhaps: http://www.jegs.com/PDFs/ARPAssemblyLube.pdf An example, if the manufacturer did the original spec based on the factory taped hole, he would have known exactly what the conditions in the hole were and wrote a spec accordingly -probably with dry thread resistance/friction in mind . On a used car, the threads may have been chased, badly re-cut,dirty,oily,have coolant ,grease,threadlock or whatever there. So how do you write a spec for that ? A competent mechanic (like JFP) uses experience and skill to find a reliable solution.The specifying engineer(if it was me) would decline to give a torque spec for the used car because I could never know what the friction was.Tell me the friction and the material and fastener type & size and yes, it is easy to give a torque range. With the M96 the limiting factor will usually be the ductility of the alloy of the block. Geeks read more here: http://www.designnotes.com/companion/manual-1.html When I rebuilt my M96 I chased and cleaned all the threaded holes .In as many as possible I used custom length s/s studs in the engine(+red Loctite) and green for the s/s nuts. There will never be a problem there ! Corrosion is a risk that compels the use of some type of lubricant/sealant/locker regardless of the torque specs. The exhaust header bolts are a good example. Yes, mine are s/s ! Last edited by Gelbster; 08-23-2016 at 01:44 PM.