ARP head studs torque?

[guyd_15]

I checked the instructions in the package, now I'm confused. I used to using headbolts (torque to 60 + 1/4 turn). the directions with the studs say 60lbs. So I call the tech line at ARP they recommend 70lbs if running boost in the 30 psi range. Now I'm really confused!
If you've hade experience let me hear it.
Guy

[BadAssPerformance]

Using motor oil on the threads instead of their moly lube, I have been using them in the 80-90 ft-lb range.

[boost geek]

I molly'd mine at 80 ft pds

[Blue Iroc R/T]

I molly'd mine at 80 ft pds

^+1 on a TIII Head

[GLHSKEN]

Molly and 85 ft lbs here... Advice from Gary D. 70 will lift the head and you WILL leak.

[Directconnection]

I checked the instructions in the package, now I'm confused. I used to using headbolts (torque to 60 + 1/4 turn). the directions with the studs say 60lbs. So I call the tech line at ARP they recommend 70lbs if running boost in the 30 psi range. Now I'm really confused!
If you've hade experience let me hear it.
Guy

The arp bolts and studs are torqued only. No 1/4 turn. I have measured the difference between the ARP moly lube, and the lube where I work.... CMD #3 high pressure lube which is much more slippery than oil, but not quite as much as the arp moly. With the arp moly lube, it took only 39ftlbs to acheive the same bolt stretch than the CMD #3 at 55ftlbs. It was a test..and only a test of the emergency turbomopar system... um..er... basically speaking: if you torque the ARP bolts to their reccomended torque, but use oil or another lube, you are not putting a sufficient load on the fastener because the friction is overcoming the actual torque. A dry thread and nut takes 85% of the available torque to overcome the friction...so you can easily see why a lube with the right coefficient of friction is important. Underloading the fastener is not good (neither is overloading)

When re-sizing rods, we use the reccomended stretch method. Most 3/8" arp's for SBC are somewheres around .006 to .0067" stretch depending on fastener model #. Under torqueing a rod bolt via wrong lube or bad torque wrench for example... the bolt stretch can be out of range with just 5 ftlbs. Look at the difference bewteen the arp moly and the cdm#3 we use as 11ftlbs difference and you can imagine that the fastener is being undertorqued. Even worse, if the machinist uses arp moly, then you assemble it with oil or cmd#3, not only ar the bolts being undertorqued, the rod housing will not be the same shape (round) as it's supposed to be. I measured a .0003-.0004 tenths difference with the arp vs CMD test.

I know you cannot measure bolt stretch on a stud in the block, but this is something to think about. 80-90 ftlbs w/oil works great for this person, but if they go 80-90 with arp moly, then it's like 100+ftlbs and the fastener could fail as well. make sure things are apples to apples and you will be fine i the long winded point I was making (and figuring someone would find this interesting

[Austrian Dodge]

i've heard it that way:
70 ft/lbs (85ft/lbs with cometic head gasket)

personally i'd torque them 85-90ft/lbs

[MiniMopar]

I ran them at 70 or 80 ft-lbs with oil (can't remember) for about 6 years with no problems. I was running about 21psi of boost back then. I used the ARP moly lube this time and torqued to 85 on an MP HG.

[GLHSKEN]

lol... Russ, You are definately safe!!

[Clay]

on the subject of studs, when you put a stud in the block, how far in the hole do you put it? IE do you let it bottom out? do you put it in 5 threads? etc?

(Im not planning on studs this go around, but the next time the head comes off, I probably will)

[boost geek]

If I remember right, the instruction sheet said to let it bottom out finger tight.
I also molly torqued at 65 like the sheet said, MP gasket lasted 5 days at 15-17 psi. Now, 80:p

[BadAssPerformance]

on the subject of studs, when you put a stud in the block, how far in the hole do you put it? IE do you let it bottom out? do you put it in 5 threads? etc?

(Im not planning on studs this go around, but the next time the head comes off, I probably will)

I would not bottom them out, but get them in there good and far, maybe 13 turns if I remember... For reference, when the nuts are torqued down, there are only a couple threads sticking out the top.

[MiniMopar]

Yeah, when I put mine in the first time, I gently chased the threads being careful not to cut new ones at the bottom and cleaned out the holes. Then I screwed them in all the way and then backed-off one turn.

I just remembered why I wasn't sure what the torque was the first time. When making the final torque, they would build-up torque and then go POP. It wasn't stripping or anything, but I think the stud was twisting in the bottom threads. When I used the moly lube this last time, that didn't happen (same block, same studs). These were the older studs that weren't "blossomed" or whatever you call it when they put an allen head in the end. Had to cut slots in them so that I could remove the head easily.

[boost geek]

I slotted mine also with a dremel tool.

[Blue Iroc R/T]

I run the studs in with a 19.2 power screwdriver (with the torque backed off some) till the studs bottom out, then back them off 1/4 turn. This leaves a good amount of threads for the nuts without leaving a lot of stud sticking up.

[Omnious]

I torqued my ARP bolts (not studs) to 95 w/moly and mp head gasket

[Directconnection]

lol... Russ, You are definately safe!!

Just so people know... I wasn't implying that people were improperly torqueing there's head studs. I was giving them food for thought.

[Directconnection]

I am told finger tight, then one of the race engine assemblers tells me that ARP reccomends 10ft lbs.

[turbovanman²]

I run the studs in finger tight, then torque to 75-80 lbs with ARP moly lube. Never lost a head gasket yet. Thats probably the only part that hasn't failed on my yet, :p

[John B]

Do you put the studs in after the head is in place or before? Or does it matter?

[turbovanman²]

Do you put the studs in after the head is in place or before? Or does it matter?

Doesn't matter. If you have a van, you can't have the studs installed with the engine in the van, otherwise you can't get the head on, :banghead:

[altered7151]

Are you guys worried about uneven clamping on the head with overtightening the studs? People have mentioned torquing up to 95ft/lbs with moly lube on a stud that is originally recommended for 70 or so. My concern is warping of the head to the point that it lifts the gasket easier. I guess the proof is in the pudding though, if its been proven to work you cant argue with it.

[turbovanman²]

Are you guys worried about uneven clamping on the head with overtightening the studs? People have mentioned torquing up to 95ft/lbs with moly lube on a stud that is originally recommended for 70 or so. My concern is warping of the head to the point that it lifts the gasket easier. I guess the proof is in the pudding though, if its been proven to work you cant argue with it.

I doubt you will warp the head overtightening it. You can however pull threads or distort the bore, I would assume.

[MiniMopar]

Yes, but thankfully studs are much easier on the block threads than bolts would be.

[guyd_15]

Thanks for the input guys. The general consensus seems to be 80-90 so I'll split the difference.
Guy

[mo' parts]

when i first installed mine, i went finger tight and then not even a quarter turn with the allen wrench. when it came time to remove them, it was a bear, they didnt want to come out. DOH!
next time i went finger tight and backed them off a little, and that seemed to work fine. i also went 90 ft lbs with the moly.