lemmysports2

iTrader: (27)

i was hoping someone could confirm torque specs of 85ft/lbs on arp headstuds with 30wt motor oil.

thanks

hopper

190k tensile strength 11 mm stud is 90 lb/feet with 30wt and 71lb/feet with moly lube. Unless you have the 220k headstuds

http://video.arp-bolts.com/catalog/ARPCatalog.pdf

page 24

lemmysports2

iTrader: (27)

thanks, much appreciated

hopper

Anytime

shadovarian

iTrader: (1)

*Sorry for this second post, when originally posted it, it never appeared so I went to another thread. Mods feel free to delete one of these posts. Sorry again*

I have put 3000 miles on my 2005 evolution 8 since I purchased it. When I bought it the car wasn't in once piece or running but the previous owner had just installed ARP head studs. I do not know what torque he used but I am certain he wasn't able to warm the car up and re-tighten (as it wasn't running).

I would like to open up the valve cover and check the ft/lbs on the studs. If I re tighten how do I go about that since they are already installed and lubed 3k miles ago?

What Ft/lbs should I leave them alone at (85 to 95?) and I am guessing if they are low then tighten to 95 ft/lbs?

Will this cause any issues being that they have been in an engine running that many miles?

GTijoejoe

iTrader: (25)

keep in mind retorque of the head studs is not necessarily the procedure rather than a precaution. There is margin within the torque spec everytime, you can't ever get them perfect... I know this because I've made OEM torque specs and the larger the spec the variation gets much larger.

That being said, do you know which lubricant the original owner used? Moly or 30wt?
That is very important as it significantly effects the clamp load hence whey they have different torque settings.

Personally I'd probably just leave them alone... you can check to the lowest torque setting to check its at the min level...but I'd not tightneing them anymore unless needed.

And just general info, if you don't know what torque setting you need for ANY of your ARP fasteners, you can always call ARP, they are extremely helpful!

shadovarian

iTrader: (1)

Molly lube was what was used so I guess I will call ARP tomorrow unless there is more wisdom to be thrown my way.

I have seen conflicting information with the molly, some say torque to 71 as above, and some to 95. That is a BIG difference.

GTijoejoe

iTrader: (25)

Wow, that is a big difference, like enough to completely yield the joint if the true setting is 71
Always with a low fruction lub like moly will the torque be less because that energy used for torque is transferred to clamp load instead of being reduced by friction. This is why there is different torque requirements, you are still sustaining the same clamp load.

When we design joints we have numerous of k-factor (friction mu) coatings to choosse from for any given application, its used to get the desired clamp load and also work with the current factory equpitment to stay within a torque range based on the application.

You can never go wrong with calling ARP if you kow all the necessary information, they should always be able to give you the correct information, I have in the past because I always loose the torque sheet lol
However, you can go wrong with listening to ppl on the internet
(I'm sure some of them are going to be right, but majority doesn't always rule)