Torque setting for ARP head studs?

I'm using ARP head studs in my engine rebuild. In the instructions that came with these studs it says :

PRELOAD (TORQUE) RECOMMENDATIONS:

[A] Torque values are based on 75% of the fasteners yield strength. Use the manufacturers torque sequence but do not use the engine manufacturers torque specs. Torque the nuts to 70ft lbs for ARP MOLY ASSEMBLY LUBRICANT or torque to 85 ft lbs with 30wt motor oil.

Due to the expansion rate of ALUMINUM, it is recommended the the torque should be 65 ft lbs with ARP MOLY ASSEMBLY LUBRICANT

What do you reckon? Should I torque the head to 65ft/lbs like ARP say or stick to the Toyota recommended 25ft/lbs plus 90° plus 90° ?

Thanks a lot.

I'm using ARP head studs in my engine rebuild. In the instructions that came with these studs it says :

 

What do you reckon? Should I torque the head to 65ft/lbs like ARP say or stick to the Toyota recommended 25ft/lbs plus 90° plus 90° ?

 

 

Thanks a lot.

You don't do 90o anything with non stretch bolts. Toyota's specs were for stretch bolts, use the specs from the ARP sheet.

you know i'm no techy (only done one headgasket and that was on a Polo!)but intuitively i'd say do it the Toyota way but with a torque wrench set to the 65ft/lbs on the first bolt that you do the 2nd round of 90 degree turns on. Then maybe back it off a little for the second bolt etc...basically to see what torque the Toyota way gives, as this may be close to the ARP recommended level anyway?

you know i'm no techy (only done one headgasket and that was on a Polo!)but intuitively i'd say do it the Toyota way but with a torque wrench set to the 65ft/lbs on the first bolt that you do the 2nd round of 90 degree turns on. Then maybe back it off a little for the second bolt etc...basically to see what torque the Toyota way gives, as this may be close to the ARP recommended level anyway?

Dude, these are none stretch bolts, manufacturers do it this way so you don't need a torque wrench.....

Someone find CW!

I've dealt with this before.

ARP recommendations all the way.

Do NOT use the Toyota tightening method, you'll do damage.

toyota say 29 lb/ft then a 90 degree turn.

ARP reccomend 65lb/ft, numerous ones are done to 80 lb/ft+.

Dude, these are none stretch bolts, manufacturers do it this way so you don't need a torque wrench.....

 

Someone find CW!

I posted before seeing your post and like i said i'm no techie, but whatever the torque i presume that the head bolts are torqued up in a certain order and that this is done gradually to not unduly stress the head, hence the 90 degree twice and not 180 degrees once. John A's comment re damage suggests to me that the toyota method would involve more than the recommended torque for the ARP bolts?, so does this mean that from 25ft/lbs Jake should be doing additional rounds at say 10ft/lbs intervals up to the 65ft/lbs.

I posted before seeing your post and like i said i'm no techie, but whatever the torque i presume that the head bolts are torqued up in a certain order and that this is done gradually to not unduly stress the head, hence the 90 degree twice and not 180 degrees once. John A's comment re damage suggests to me that the toyota method would involve more than the recommended torque for the ARP bolts?, so does this mean that from 25ft/lbs Jake should be doing additional rounds at say 10ft/lbs intervals up to the 65ft/lbs.

Its very difficult to ive torque on stretch bolts as they... well stretch!

Sequence from memory is first one nearest the intake cam gear then diaganol in turn from there.

Use the Toyota tightening sequence (i.e which bolt first. which blt second, etc) but use the ARP final torque. Wouldn't hurt to do it in two stages.

OK. Thanks everyone.

i read on supraforums a lot had tightened to 80 ft/lb whearas ARP reckon 65 so i split the difference and went just over 70 ft/lb been on nearly a year with no probs

Use the Toyota tightening sequence (i.e which bolt first. which blt second, etc) but use the ARP final torque. Wouldn't hurt to do it in two stages.

Yeah that's what I meant --- I thought it was clear.

The SEQUENCE is the Toyota one --- actually the standard one for cyl heads in general.

The final torque value is the ARP one (depending on thread lubrication).

And yes, I'd do it progressively in 3-4 stages.

I've had a friend torque these up to 85lfbt with no drama (cometic gasket), so even if you go a bit higher it won't self-destruct:)

But if it were mine I wouldn't go more than 5lbft over the recommended value by ARP. They know what metals they use and know how their materials behave better than anyone else.

OK, I'll go with the ARP recommended torque.

One more thing. Lucy said the stock head bolts are stretch ones implied that the ARP aren't. So that means the ARP ones are reuseable, does it?

People reuse them time and again.

(actually it tends to be people who take their heads off like a yoyo he he...)

OK, I'll go with the ARP recommended torque.

 

One more thing. Lucy said the stock head bolts are stretch ones implied that the ARP aren't. So that means the ARP ones are reuseable, does it?

INspection always advised but yes you can reusethem, always best to measure them tho.

I torqued mine down to 100 ft/lb. depends on whether you have the L19 studs or not.

I torqued mine down to 100 ft/lb. depends on whether you have the L19 studs or not.

And a large wallet!

Sorry was I talking to you.

Sorry was I talking to you.

Sorry my Bad.

No, im sorry, bad mood, harness wiring gets to me sometimes. lol

Any fastener that isn't thightened beoynd its yeild point can be re-used.

Just a word on these ever-increasing torque figuires: If you go too high then stud material aside, you run the risk of localy yeilding the aluminium in the head bolt boss, in which case the clamp load will come off the fastener anyway.

If someone can post up the washer diameter and thread diameter of the ARP head bolts I can have a bash at working it out. I think the material properties are on the ARP website.

Any fastener that isn't thightened beoynd its yeild point can be re-used.

 

Just a word on these ever-increasing torque figuires: If you go too high then stud material aside, you run the risk of localy yeilding the aluminium in the head bolt boss, in which case the clamp load will come off the fastener anyway.

 

If someone can post up the washer diameter and thread diameter of the ARP head bolts I can have a bash at working it out. I think the material properties are on the ARP website.

They have two types of material. ILl scan and post teh full spec sheet from a set I have here.