I was just wondering if ARP head studs need to be re-torqued after like 500 or 1000 miles on a new build (Turbo H22A)? Just for the record, these are brand new head studs and everything was correctly assembled and torqued in 3 steps as required...

Just wondering on a rainy day lol...

 

I would guess yes but would like this answer also for my ls-t build

 

Email ARP... Please post up what they say.

 

Well, they can stretch, vibrate loose or your head could possibly lift so it is a good idea to ask this question. See what ARP says, hopefully they can shed some light on it themselves but I'm sure a number of members will add some clarity here.

 

arp does recommend so

 

You really don't need to re-torque them as long as you followed the specs provided by arp to begin with. I have never seen anyone have an issue when they didn't re-torque their head studs.

 

Thats weird as I called them when I was building my motor about this and they said no. In for some updated answers as this was a year ago.

 

Mtber, yes I torqued them down in 3 equal steps and in proper sequence according to the service manual. Also, chased all threads and coated with the recommened arp lube I guess it makes sense since these are basically "performance" studs just as you can re-use them a few times unlike stock studs.

 

As far as I know they can be re-used but it's ideal to measure them to make sure they haven't stretched.

 

The studs are what come loose on me, not the nuts. ARP says "finger tight" which is garbage. I torque the studs to 15ft-lbs into the block first and no longer have studs coming loose. I dont re-torque anymore.

 

Wouldn't tightening the nuts tighten the studs?

 

i had issues with arp studs in the past....they do work well but their hand tight installation method is kinda sketchy.....i had some coolant leaking issues and one time i found all head studs loose when i took it apart....

switch to GE studs with the dog point bottom and torqued them into the block. never had an issue since....

 

I use GE on my own car and recommend GE on all our customer Cars.

Not a problem with a single one.

 

UPDATE : I emailed ARP today cos I had some time and was on their site and whoa - here is the final answer ...

"Yes it's recommended that you re-torque after it's been run up to
operating temp and let cool completely down."
RonF

 

If you use the arp thread lube you shouldn't have to re-torque. I've made 700+whp and 2000miles later without re-torquing it's fine. They just say that to cover their ***

 

Yes, one thing I must say I had many fantastic offers on used and "slightly" used head studs but although at the time my budget was tight, the one thing I did was buy them brand new I did not want to feel "nervous" about something so critical as this - so Yes, I did the following...

1. Chase / Clean threads in block and even new studs.
2. Use the ARP thread lube as directed (they provide more than enough btw )
3. Tighten studs into block so they are just snug
4. Put on head and tighten as directed, in proper sequence 30, 60 and 90 ft lbs with my Snap-On Torque Wrench (Sorry I had to rub the Snap-On in, I just got it and love it hehe)


So you think I should be ok? Car (Turbo Built H22A) is not gonna make more than about 420Whp at most for a long long time. It sure is a pain in the *ss to re-torque the bolts considering the cams have to be removed, etc. and its in an EG which makes other factors more of a pain...

 

You should be fine. If its not to much of a big job to check/re torque them then do so. I'd check them if it was my car.

 

Yeah, get out your 9 inch mic or whatever they are removed, and measure that stretch.....how many people even have access to one?

 

Well I decided to search outside of HT since ARP's go into alot of other makes too. I was glad to see that even on DSM, BMW, Ford and a bunch of other tech forums that it was not really required to re-torque bolts that have been installed WITH the arp assembly lube they come with. So I guess we are all good then provided the arp lube was used

 

ARP bolts/studs DO NOT PERMANENTLY STRETCH. They ONLY stretch when you tighten them. They are like springs. Once properly torqued, it is this spring tension that keeps the mating surfaces tightly together. Once you remove and untorque the bolts/studs, they will return to their exact manufactured length. If you're holding an ARP bolt/stud in your hand (i.e. it's not torqued), and it differs from the manufactured length by even 0.001", then it means you over-torqued it at some point and stretched it past yield. In which case it's garbage and you should throw it away.

FYI, I always use a digital caliper to measure the exact length of all my head studs and rod bolts, and I keep these lengths written down in a log somewhere. If I ever have to tear down the motor for whatever reason, I re-measure the bolts with a caliper and make sure they haven't stretched.

Bolts should NEVER permanently stretch, period! That's why it's imperative to use a rod-bolt stretch gauge when you install new rods. Torque wrenches aren't worth a damn on sensitive areas like rod bolts. I'll often have to torque the bolts up to 20% higher than the listed torque-spec, just to get the proper stretch.