ARP Head stud questions...

[naviathan]

Two quick questions:

1. Do I need to worry about any water jackets leaking through the studs that might require me to get the ARP thread sealer or am I good to go with the thread lube?

 

2. Tried emailing ARP about this, but go nothing back. Will the torque specs stay the same or should I pick it up a bit because of the MLS Head Gasket and upped compression?

[zcar?]

I did not put any in mine and I have no leaks. Just screwed them in and put the head on.

Jeremy

[blue72]

Based on my experiences, I don't believe that any of the head bolts on the L6 enter water passages. I searched our forums, and that is the general consensus here as well.

I wouldn't torque the ARP hardware any further than recommended either. There are also discussions on this forum and other places on the net that talk about yeild and stresses put on threads.

[BRAAP]

1) L-series head bolt holes are blind, i.e. they do NOT go into the water jacket. No sealer required. Install the studs in the block finger tight only. Some prefer to install the studs finger tight in the block then back them out 1/8-1/4 turn after they bottom so that all stress upon final torquing is on the threads only, no loads/stresses on the stud chamfer or bottom of the hole. 6 one, half dozen the other. Do use motor oil or anti seize on the portion you thread into the block to ease removal in the future. They should come back out with your fingers if and when that time arises.

 

2) Follow the ARP Torque spec to the letter, do NOT deviate from the ARP torque spec recommendations! They typically list two different torque specs, one with motor oil, the other with their assembly lube. The torque spec is specific to the fastener, regardless of the part being clamped or any gaskets used. The idea is to get the fastener, (bolt or stud), to the point is starting to stretch, and in this stretched springy tension state, is where the fastener is best used. It wont come loose, and it is just short of it yield. We joking refer to over tightened fasteners as bubbas torque spec called, “race tight”!

 

3) 1 fast z may want to add his input on this well, if so, follow his advice.

 

Hope that helps,

Paul

[naviathan]

1) L-series head bolt holes are blind, i.e. they do NOT go into the water jacket. No sealer required. Install the studs in the block finger tight only. Some prefer to install the studs finger tight in the block then back them out 1/8-1/4 turn after they bottom so that all stress upon final torquing is on the threads only, no loads/stresses on the stud chamfer or bottom of the hole. 6 one, half dozen the other. Do use motor oil or anti seize on the portion you thread into the block to ease removal in the future. They should come back out with your fingers if and when that time arises.

 

2) Follow the ARP Torque spec to the letter, do NOT deviate from the ARP torque spec recommendations! They typically list two different torque specs, one with motor oil, the other with their assembly lube. The torque spec is specific to the fastener, regardless of the part being clamped or any gaskets used. The idea is to get the fastener, (bolt or stud), to the point is starting to stretch, and in this stretched springy tension state, is where the fastener is best used. It wont come loose, and it is just short of it yield. We joking refer to over tightened fasteners as bubbas torque spec called, “race tight”!

 

3) 1 fast z may want to add his input on this well, if so, follow his advice.

 

Hope that helps,

Paul

Awesome reply, thanks Paul. I haven't been able to find ANY torque specs for these studs. The documentation that came with them just covers the threading process and not the torque.

[blue72]

I've still got the box for my L6 ARP head studs around somewhere if you can't find the specs on the paper, or if no one else chimes in here.

[BRAAP]

I just happened to have a new set of L-6 ARP head studs. SPec sheet has the torque value at the bottom, highlighted in Green in the pic below. Torque value is 60 ft lbs with the ARP lube. No mention of torque value with motor oil, sorry. Some instances such as rod bolts, they offer both, torque spec with motor oil is always higher.

 

If you don't have the ARP Assy lube, you can usually get it from most auto parts stores that sell and/or stock ARP fasteners. ARP part number for the lube is 100-9902

 

ARP contact info;

ARP

1863 Eastman Avenue

Ventura, CA 93003

Hours: 7:30am - 4:30 pm PST

Will Call Hours: 8:00am - 4:00pm PST

Order Desk & Technical Support: 800.826.3045 or 805.339.2200,

fax: 805.650.0742,

info@arpfasteners.com

Sales & Marketing: 805.339.2200

 

Hope this helps…

Paul

 

[naviathan]

Awesome thanks for the info. My box came with assembly lube so I'm good on that.

[cygnusx1]

Avoid using motor oil on the nuts if at all possible. If you don't have the ARP lube leftover, use the gray/silver anti-sieze lube or moly based grease. I found that engine oil binds the nuts up and prohibits a smooth rotation which is a MUST for accurate torque application. Somewhere in the ARP literature I also read that after a couple of re-uses, the torque values needed to apply the correct stud stretch, drops. This is due to the thread contact surfaces smoothening out from usage.

 

They also claim that the BEST method is to use a measuring tool, and to torque the studs to a pre-determined proper stretched length. I don't have the actual length numbers but I'm sure ARP could provide them to you. 99.99% of the people don't have access to such a measuring/torquing device though this would be by far the most accurate way of assuring proper tension.

[Daeron]

Step 5 on that sheet says at the beginning to use ARP Moly assembly lube or other good quality moly based lube, then later says SPECIFICALLY not to use any other brand moly lubricant.. Whats with that?

[cygnusx1]

The problem is that the torque required to stretch the bolts varies depending on the lubricant used. ARP has no way of throwing a torque number at you unless they know the coefficient of friction in the threads. When using their grease, they have solid test data to back up their torque specs. I used that gray anti-sieze paste on my second install and found it very smooth. I went to 70ft-lbs with the anti-sieze paste since I couldn't find moly-grease at my local "chrome-stuff-bling-only" auto shop.

 

Take a quick read through this PDF file. Torque-vs-Tension on studs for various lubes. It's a bit of an advertisement but it demonstrates the point.

 

http://www.altboron.com/tech_data/pdf/fastenertorque-tensiontestsusinglubrisilksyntheticgrease.pdf

[junglist]

Step 5 on that sheet says at the beginning to use ARP Moly assembly lube or other good quality moly based lube, then later says SPECIFICALLY not to use any other brand moly lubricant.. Whats with that?

 

I don't know whats up with that but I do know that I was kinda annoyed to spend $150 on some bolts and get a photocopied instruction sheet that was cut out crooked. I think they could do a little bit better.