ARP Head bolts

[SFRacingGST]

was wondering if arp head studs should be changed every time the head is removed? Mine are only 1 year old and only torqued once... I know with the stock ones you are suppose to change them because they strech when torqued, is this the same a the ARP ones?? Or since they are so strong they can be reused??

 

[Staytuned]

I would reuse them if they were torqued to ARP specs, but not if they were torqued like most DSMer's prefer (90+pounds). I am very over cautious though when it comes to stuff like this. I am pulling my head and swapping a built 1g head on this winter and I am using a new HG and ARP'S.

 

[SFRacingGST]

Well in engine class they say NEVER REUSE HEAD BOLTS. I was wondering if it was any different for ARP head bolts seeing they are much stronger... I am also doing a 1g head swap this winter and probably doing to go with new ones... I e-mail ARP to see what they say... Any more opinions?

 

[92awddsm]

ARP headstuds are reusable. I have had my head off more than 5 times over the past 7 years and still using the same studs with no issues what so ever. The only headbolts that are not reusable are torque-to-yield bolts. ARP bolts will eventually over stretch with repeated tightening and need to be replaced but since this is only your first removal, you will be fine. You should replace them after 6-7 head removals if you torque to manufacturers specs. If you exceed the torque specs, you run the risk of overstretching the stud, breaking the stud, or pulling the threads out of the block. Stick to arp torque specs and you should have nothing to worry about.

 

[talon187]

arp head studs are reuseable if they didnt strech i would look at them very close and see if they streched because they can if they didnt strech go for it but if they did buy a new set

 

[prostreetdsmx1]

absolutely reusable. Now you should definitely inspect them before you put them back in. We did see a set stretch on an EVO after the snapped when the customer was torquing them down. Always check to be safe but generally it is just fine.

 

[92awddsm]

absolutely reusable. Now you should definitely inspect them before you put them back in. We did see a set stretch on an EVO after the snapped when the customer was torquing them down. Always check to be safe but generally it is just fine.

Liam, huh? I remember that. Overtorquing was the cause of that, wasn't it?

 

[prostreetdsmx1]

Liam, huh? I remember that. Overtorquing was the cause of that, wasn't it?

yeah. I still remember the look on his face when he was listening for the click of the toque wrench but got a snap instead.

when we finally were able to get it out the stud looked quite stretched.

 

[92awddsm]

yeah. I still remember the look on his face when he was listening for the click of the toque wrench but got a snap instead.

when we finally were able to get it out the stud looked quite stretched.

And if I remember correctly, he was using trying to torque the 11mm studs to the 12mm specs. This is a perfect example of why you dont exceed manufacturers torque specs. Increasing torque a few lbs above what is set by ARP may sound good, but it can be a disaster.
Follow specs as if you have never touched an engine and you will be fine. Those of you that feel you know more than arp, forget it, you dont. If you feel that your studs need 15ft/lbs more torque than what is on ARP's spec sheet, you have no business being under the hood of a car, period.

 

[SFRacingGST]

see, the only bad thing about this is that i didn't torque them the fisrt time, i had the clowns at pruven put a new block in and they torqued them for the 1st time, and they had never been messed with untill now... Should i just re use them or say f it and get a new set??? Let me know what i should do

 

[phillabaum03]

Reuse them they will be fine. Unless you really want new ones i know alot of ppl that would want them and wouldn't think twice about using them.

 

[99gst_racer]

Over torquing causes over stretching, which can cause permanent deformation, and that would be the determining factor whether or not a set of head studs is reusable or not. Recommended torque is equal to 75% of the fastener's yield strength. Increasing the torque amount will increase the risk of compromising the fastener and taking it beyond it's yield strength.

If an un-torqued fastener is permanently stretched .001" or more from it's original length, it is considered "failing" or "failed" and should be replaced immediately.

 

[SFRacingGST]

I am alittle confused. Do we have to use the thread sealer on a 1g dsm? If so where can i get some? The 1g ARP Head Bolts are 12mm, Correct? So according to the Box it says i should torque it to 86lbs using the Haynes manuel torque sequence. how come (http://www.dsmtuners.com/forums/attachment.php?attachmentid=52917&d=1119319739) Says 80 lbs, and they guy from ARP told me for my specific application i should torque it 75lbs?

So i guess my questions are... Do we have to use the thread sealer, or can we use just the molly lube and What should i torque my 1g 6 bolt ARP head Bolts to?

 

[daren_p]

You only need thread sealer if the stud enters a water jacket, so no you don't need the sealer. I believe ARP gave two specs for the 12mm studs, 80 was the origional spec & the new spec is 86 ft/lbs. The 75 ft/lbs spec that the guy from arp is refering to is more then likely for the 11mm studs, as if I recall correctly thats the spec mine called for. I would go with the 86.

 

[SFRacingGST]

Thanks for the re-ply... So use the molly lube on the studs and the nuts, and put the studs in hand tight until they bottem out? Thanks

 

[daren_p]

Yes, use their molylube but to install the studs this is what I did. First run the studs all the way down and go up & down a few times to make sure the threads are all clean & the stud is bottoming out, I used abit of force with an allen key to do this. Then losen the stud of & tighten it down with ligh pressure till you feel it bottom out. Once your at that spot, then back the stud off about 1/4 turn. This way you have no torque in the stud to effect the reading. Thats the way I was told to do it & it worked perfect for me.

 

[SFRacingGST]

good info, thanks alot, i just wanted to make sure it all gets done right... One more question, i got a new metal head gasket. Should i torque it all down once using the correct sequence to 30 then to 60 then to the 86? Others have mentioned doing that a few times... any suggestions??

 

[daren_p]

Ya that seems alright, most do it in 3 steps. You may want to make the second last torque spec abit lower as you want the last step to have the higher increase, to make sure the final spec is correct (as it takes more torque then your previous torqued value to get the fastener moving again). So maybe do 50 or 55, then 86 for your final.

 

[SFRacingGST]

One more question about the torque, I was talking to the guy from ARP again today to order new nuts with smaller flanges on them and i asked him how much i should torque it to since the package say "The torque values represented here intended to be for general information, not for specific installations". I gave him my part number of the 1g 12mm head studs (207-4201) and he said to torque it to 75lbs. I know i kinda already asked this earlier in the thread, but shouldn't i torque it to the 75lbs thats application recomended even though the box said 86lbs? Let me know some oppinions please, what have other people done in the past for torque on a 1g ARP?

 

[Tony90TSI]

The torque specs are different for the same stud based on lube used. If you use no lube then you need to apply more torque. Greatest to least.

Dry > Motor Oil > ARP Lube

 

[SFRacingGST]

Well the rep said with the ARP moly lube you should torque it to 75 lbs. Was just wondering what other people have torqued theirs to for a 6 bolt.

 

[turbo addict]

105 on moly lube, zero problems on many 6bolts, I run 32-35psi on race gas and still have a stock head gasket.

 

[romeen]

105 on moly lube, zero problems on many 6bolts, I run 32-35psi on race gas and still have a stock head gasket.

While exceeding ARP's recommended torque specs will hold great it will make future reuse of the studs questionable. This is according to ARP.

 

[dnhieu]

this is VERY true but i look at it like this. How often will you be pulling your head???? if i can get 2-3 uses out of them im happy. i just torqued mine to 100 ft lbs...

 

[romeen]

this is VERY true but i look at it like this. How often will you be pulling your head???? if i can get 2-3 uses out of them im happy. i just torqued mine to 100 ft lbs...

You do have a point with regards to how many times is the average DSM owner planning on removing and replacing the head. I know I have no plans to do this multiple times (knock on wood ).

However, if tightening to ARP's recommended torque specs will hold tight to pressures well beyond what even the largest DSM turbos can produce then I see no point in exceeding those specs.