Quote:
Originally Posted by piper6909
When the Porsche engineers specified a certain torque, was that with or without ARP lube? If ARP makes such a big difference, will you get the actual clamping force the engineers intended or, since ARP makes it easier, more clamping force than intended? Just a thought.
Yes, you want a little Lube on the bolts so they don't bind and "creak" when you torque them down, because if they do you won't get the true torque and less clamping force than intended. Would using ARP have the opposite?
I noticed that the label says it's "specifically designed for ARP fastener preload specs."
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That has been an internet argument for years. Running my own business, as well as building race cars and engines for various racing venues over several decades, I am super critical about two things when it comes to torque specs: accuracy and reproducability. From everything I have read, and what I have learned myself, sometimes at considerable expense, a lubricated fastener will both attain the correct clamping force, and that clamping force can be accurately be repeated as necessary. Now that thread lubrication can come in many forms: thread locker, anti seize, or simple lubricant; all will provide some level of lubrication during assembly, and not all will provide the same degree of lubrication, but all provide some level, which is the improtant point. In their white paper, ARP discussed at length about finding both erradic and lower clamping pressure than desired when threads were assembled dry and torqued to a given spec, and higher and vastly more consistent clamping pressure when the treads were lubricated and torqued to the same value.
Yes, I have read, and often laughed at, internet stories about people having their wheels fall off because they use anti seize on the lug threads. Anti seize on the lugs both prevent thread galling over time, and incorrectly torqueing the fasteners. I litterally have no idea how many cars we have running around with anti seize on the wheel lugs, but I can tell you that none ever came back because either the wheel fell off or was damaged by excessive torque. Same can be said about engines we either worked on or built for customers. I can tell you that I have seen brand new and very expensive engine cases that demonstrated unequal drag when simply threading in new bolts or studs with my fingers. This one of many reasons why we always "chase" every threaded opening in an engine case before assembly, and use a small dab of ARP thread lubricant when assembling. Consistency matters.