The instructions that came with my bolts made no mention of re-torquing after assembling the engine, but their FAQ list says to re-torque them after running the engine up to temperature. What should I believe?

I know some engines normally require re-torquing after running the engine, but I don't think the 6.9L is one of them. I did go throught the torque proceedure several times when putting the engine together, but have not touched the bolts since.

 

I would think not.

How many mile do you have on her now?

Do you have the boost cranked up on it? What are the EGT's doing?

 

500 Kilometers at the moment. Boost only goes to 4-5 Psi under normal driving conditions, and maybe 7-8 if I really try. EGTs have been up to 850 so far. Its just been the break in runs or other light rinning so far, haven't had to do any towing or long haul running at high speed yet.

 

I checked mine, none of the nuts turned before the torque wrench clicked.

Checked a second time after four months, still the same, clicked before the nut turned.

 

Good enough then, thanks.

 

When you say sevral times, did you follow the instructions for new studs, of torquing and releasing something like six times before final torque.

 

i did it 3 times actually, and that wasn't in the instructions either.

 

This is from the installation instructions page of arp's website
Using a Torque Wrench



If the stretch method cannot be used in a particular installation, and the fasteners must be installed by torque alone, there are certain factors that should be taken into account. ARP research has verified the following “rules” pertaining to use of a torque wrench:

1. The friction factor changes from one application to the next. That is, the friction is at its highest value when the fastener is first tightened. Each additional time the fastener is torqued and loosened, this value gets smaller. Eventually the friction levels out and becomes constant for all following repetitions. Therefore, new fasteners should be tightened and loosened through several cycles before applying final torque. The number of times depends on the lubricant. For all situations where ARP lubricants are used, five cycles are required before final torquing.

2. The lubricant used is the main factor in determining friction, and therefore, the torque for a particular installation. Motor oil is a commonly used lubricant because of it’s ready availability. If less friction is desired in order to install the fasteners with less torque, special low friction lubricants are available. With special lubes, the required torque can be reduced as much as 20 to 30 percent. It is important to keep in mind that the reverse is also true. If the torque value has been specified for a particular fastener on the basis of low friction lube, installing the fastener with motor oil will result in insufficient preload; the torque has to be increased to compensate for the extra friction caused by the motor oil.

3. Surface finish is also important. For example, black oxide behaves differently than a polished fastener. It is therefore important to observe the torque recommendations supplied with each fastener.

NOTE: It is possible for even the most expensive of torque wrenches to lose accuracy. We have seen fluctuations of as much as ten (10) foot pounds of torque from wrench to wrench. Please have your torque wrench checked periodically for accuracy.

 

My directions did specify 5 times, so I did torque mine down using four steps to reach the final torque rating, then removed them using four steps four times before I did the final install.

Molly assembly lube applied sparingly was also my lubricant.

I noticed the final install was almost a complete turn of the nuts more than the first install was.

 

I used the lube that was supplied with the bolts. Right now the most boost I have seen is 6 psi. If I ever mod the turbo or find some other way to get into the mid teens, I'll probably recheck the bolts. I'm still trying to figure out how to get 10 psi under 2000RPM....