ARP rod gage

[022spa]

In the event of an overrev,
can rod bolts be replaced with ARP bolts.
Or can the ARP gage fit onto a bolt with out splitting the case?

[304065]

You can replace the bolts without splitting the case but if the engine was over-revved and damaged, it's a good idea to spend the extra few hours and split the case.

The gage cannot fit on the bolts without splitting the case, there's not enough room. See my recent thread on engine assembly to see why, you just can't fit it inside. That said, you could use the torque method with the rods in a vise and then repeat the torque to approximate the proper stretch.

[BoxxerSix]

Yea, the ARP gauge it too thick to fit the case and get straight alignment on the bolts. Personally, I say split the case and check a few things out before going through the trouble of putting it all back together only to find something wrong internally. It's not much work to proceed to that point once the P&C's are off.

As long as you have ARP moly lube you can do the triple torque method to get to the correct torque as stated:

Torque
Break
Torque
Break
Then Torque again to final spec

This ensures the bolts area seated on the rods and stretched as close to their final spec as possible.

This ONLY works with ARP moly lube. If you don't have it, get it. You really should use it if you use the stretch gauge and most definitely need it if you use the triple torque sequence. If you haven't had your torque wrench calibrated in awhile now is a good time

[304065]

I agree with part of that, if you are using the "tighten and loosen three times before final torque" method, the ARP lubricant is important. When you are tightening and loosening the bolts before the final torque, you are burnishing the threads, e.g., there is microscopic roughness on the surface of the bolt and nut which causes friction, which can cause the torque wrench to click before the stretch value is reached. Assembling and disassembling three times allows the parts to wear in against one another, reducing the friction value presumably enough to allow better repeatability in approximating the correct stretch with the torque method.

If you are using a stretch gauge, it doesn't matter whether you burnish or install dry or use ARP assembly lube or loctite or plain old oil. This is because the stretch measurement is independent of the torque that is required to get there.

When I stretched my bolts I found that the required torque was higher than that originally used to achieve the same stretch. Why would that be, did the bolts get rougher? No, it's because it was colder and the thread tolerance was closer and the lubricant on the bolts was thicker, it all adds up. 4% error on a torque wrench reading 55 Ft-lb is 2.2 ft-lb, which is pretty hard to measure in the average garage.