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Tip For Those With RaceWare Head Studs
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flosho  



Joined: 01 Jul 2004
Posts: 3153
Location: Eau Claire, Wisconsin

PostPosted: Sat Jul 12, 2008 4:29 am    Post subject: Reply with quote

Dan, do you have that coupon code? I didn't see that, but maybe i'll call them and see if they'll take 30 dollars off my order.
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ideola  



Joined: 01 Oct 2004
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Location: Woodstock IL

PostPosted: Thu Jul 17, 2008 10:18 pm    Post subject: Reply with quote

Just placed my order.

Flosho, I think the coupon code is personalized. The flyer I received has the following info above my name and address:

T253 P3
ZF30657675

The lower number was the "coupon code" I entered, so I doubt that it will work for anyone else. I would simply recommend that you call Summit and ask them if they will extend the special to you.
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flosho  



Joined: 01 Jul 2004
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Location: Eau Claire, Wisconsin

PostPosted: Sat Jul 19, 2008 6:36 am    Post subject: Reply with quote

So what are the torque values for the ARP head studs? Do we use the OEM specs or some other?
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ideola  



Joined: 01 Oct 2004
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Location: Woodstock IL

PostPosted: Sat Jul 19, 2008 7:06 am    Post subject: Reply with quote

That's a good question, Flosho. My box arrived today, but I'm jumping in a cab momentarily and can't check to see if they packed instructions or not.

In any event, I was going to post that I confirmed earlier that there is absolutely NO issue with fitment, as Steve attested earlier. These are the cat's meow, especially for $130.
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bass gt  



Joined: 02 Dec 2004
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Location: Johannesburg for now!!

PostPosted: Sat Jul 19, 2008 7:14 am    Post subject: Reply with quote

Torque up to 85ft/lbs in 3 steps. say 40 then 60 then 85. make sure you use the ARP assembly lube and not motor oil. then recheck once after running the engine and cool. back to 85ft/lbs. And believe me, you won't get better.
Thanks and renumeration to................

Steve
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Smoothie  



Joined: 01 Jan 2003
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Location: DE (the one near MD, PA, NJ)

PostPosted: Sat Jul 19, 2008 8:09 am    Post subject: Reply with quote

flosho wrote:
Do we use the OEM specs or some other?

Head studs (both Raceware and ARP) use a lower torque number because the threads at the upper end are finer than the oem head bolt threads. If you used oem bolt torque specs on the finer threaded studs, you'd actually be applying way more clamping force, stretching the studs more than they should be, and coming closer to pulling the threads out of the block. Just how close and how much a danger there'd be of pulling the threads out I don't know, but you'd be getting closer to that scenario by using bolt specs with studs.
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flosho  



Joined: 01 Jul 2004
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Location: Eau Claire, Wisconsin

PostPosted: Sat Jul 19, 2008 11:35 am    Post subject: Reply with quote

So, I tried to install the head today, got everything lined up but the back bottom head stud wont fall into place, I'm thinking its because of the head centering bushing?? It was the only hole that had the little extra piece on it. It was on the cylinder head actually and not in the block? Any tips on this subject? All other 9 went in fine?? I haven't put the nuts on yet, could be that if i twist the nut on down that one it will continue to thread in?
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bass gt  



Joined: 02 Dec 2004
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Location: Johannesburg for now!!

PostPosted: Sat Jul 19, 2008 7:25 pm    Post subject: Reply with quote

From memory there is no issue with the little had locating clips, unless yours is deformed slightly and wont let the stud throgh. Don't wind the nut on until you have bottomed the stud.
I have actually stopped using the rear locating clip. I now fit the stud into the block in the top left end, fit the gasket, use the front clp to locate it all. Then with the head swung up, slide it down the rear stud, then as it is close to the block, swing it down and locate it on the front clip. This means you are not juggling the head around trying tpo find the two clips to locate the head. Then drop in a couple of studs to hld the head, and you're set. All in all, much easier process. Of course, you need to have the inlet manifold removed et, but it is well worth it. Make dropping the head on a snap, as opposed to sliding it around to find the lugs, realising the gasket has dislodged and starting again
Smoothie, 85ft/lbs is 85 ft/lbs. You don't use lower torque values. As you say, the ARP studs have a fine pitch on the top thread. This allows a greater tensional force to be applied. It also allows the stud to stretch in a more controlled manner. But the clamping force is that which you apply via the top nut. And if you wind the ARP studs to 85, or the stock nuts to 85, you are still applying 85. The ARP studs can take significantly more than 85 though. Also, there torsional strength is much better, so the posibility of the head lifting under high boost/compression is greatly reduced. If you look at the torsional strength values of a stud vs a nut vs a bolt&nut, the stud is way ahead on strength. The advantage of these studs is that a more controlled clamping force can be applied, the studs stretch is a more quantified amount, so there is less likely hood of head lift, and as they are significantly stronger than the stock item, an additional 5/10ftlbs can be applied if required. But, all studs must be bottomed evenly to ensure equal loading. If one stud is only 2/3rds down into the block, this will put unequal strain on the bottom thread pitches of that stud and change it's stretch characteristics. So before you fit these studs, make sure you run a tap down the hole to clean the thread, and test fit each stud into a hole so that you can confirm that they all bottom equally. And use LOTS of the AP aasmbly lube. I would recommend buying an additional 4oz pot, to be on the safe side.
In this picture, you can see i have fitted the studs into the block, and am ready for tightening down. I even wound them down to an equal torque of 15ft/lbs with the integral allen socket and then measured each one for it's height off the deck. Then when i fit the head, i repeat this process, by torquing down the stud, and taking a measurement from the washer seat in the head to the top of the stud. Details, details, details. The devil is in the details. of course, this is only necessary if you are building a high HP motor, but it is best practice, so i would recommend it to all. And remember, NECER snatch or tug at the torque wrench to get the click. Use a steady, even pull to set the value. Repeat 2-3 times to be sure, but NEVER, EVER snatch or tug. And for these nuts, buy yourself a good quality 12 point socket. And use LOTS of lube!!!!


Steve
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Rasta Monsta  



Joined: 12 Jul 2006
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PostPosted: Sun Jul 20, 2008 1:05 am    Post subject: Reply with quote

That's interesting. . .I always thought studs weren't supposed to be bottomed. . .
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Smoothie  



Joined: 01 Jan 2003
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Location: DE (the one near MD, PA, NJ)

PostPosted: Sun Jul 20, 2008 3:03 am    Post subject: Reply with quote

bass gt wrote:

Smoothie, 85ft/lbs is 85 ft/lbs. You don't use lower torque values. As you say, the ARP studs have a fine pitch on the top thread. This allows a greater tensional force to be applied. It also allows the stud to stretch in a more controlled manner.

Well obviously they've been tried and true to handle up to 85ft-lb and that's good, but the instructions with my Raceware studs (which shouldn't differ too much from other makers) call for a final torque of 60 ft-lbs. They have you tightening in 3 steps - 40Nm.(30ft-lb), 60Nm.(45ft-lb), then 80Nm.(60ft-lb).
Here's their answer to why lower torque is used with the head studs -

bass gt wrote:
But the clamping force is that which you apply via the top nut. And if you wind the ARP studs to 85, or the stock nuts to 85, you are still applying 85.

One of us (and it's not necessarily you) is confused on the use of the term "clamping force". My thinking is that it refers to force that the bolt or stud assembly applies in pulling parts together (similar to your use of the term "tensional force"). Your use of "clamping force" seems to be equivalent to torque - or the amount of -rotational- force applied to tighten or required to loosen..

Raceware also mentions in their Tech Q&A that their studs "are not permanently stretched when properly tensioned". To me, this suggests that if their recommended torque is exceeded, the studs may permanently stretch, then require replacement instead of allowing re-use in the future..?
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Smoothie  



Joined: 01 Jan 2003
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Location: DE (the one near MD, PA, NJ)

PostPosted: Sun Jul 20, 2008 3:13 am    Post subject: Reply with quote

Rasta Monsta wrote:
That's interesting. . .I always thought studs weren't supposed to be bottomed. . .

The raceware instructions say to use "a very light coat of teflon based liquid pipe sealant on the coarse threads of the stud before installation into the block. (The sealant is used merely to hold the stud in place if you remove the nut and washer at a later date.) We do not recommend using loctite on any of the threads!!!)

The studs should be threaded in by HAND ONLY until they bottom.
"
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bass gt  



Joined: 02 Dec 2004
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PostPosted: Sun Jul 20, 2008 4:45 am    Post subject: Reply with quote

Smoothie,

I was getting my tensional and tonsionals in a twist
Re the ARP studs, i'm prety sure the paper that cam ewith them spec'd them at 85ft/lbs. Perhaps Dan can assist here.
Re the stretching of the studs, i have recorded the lengths of each stud using a didital vernier. When i pull the head, I check the allowed values. Allegedly, the ARP studs will "shrink" back to original length if left without tension for a while. So i have 2 sets that i rotate when i pull the head.

Steve
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flosho  



Joined: 01 Jul 2004
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PostPosted: Mon Jul 21, 2008 7:39 am    Post subject: Reply with quote

Ok guys, on the back of the box, it has the specs for all their studs/bolts.


the "12 mm stud" has an option for 77 ft/lbs, 86 ft/lbs, or 96 ft/lbs. This is depending on the "fastener tensile strength" in either 170,000/180,000 psi or 190,000/200,000 psi, or 220,000 psi, respectively.

Meaning, if i want it to hold 200,000 psi, i should torque the head stud nuts to 86 ft/lbs.

All these torque specs assume using ARP assembly lube, they are higher if you use 30 wt motor oil.


I'm just going to torque these things to 86 ft/lbs. I'm guessing if I tighten them more, its going to take a catastrophic disaster to lift the head.
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Smoothie  



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PostPosted: Mon Jul 21, 2008 9:30 am    Post subject: Reply with quote

Someone please correct me if I'm wrong of course, but I think the tensile strength ratings don't change - they're a set number depending on the strength of a fastener (a characteristic of its' material, size, and hardening). -So a 170k-180k psi ARP stud can be torqued to 77 ft-lb, a 190-200k psi torqued to 86 ft-lb., etc.
I'm pretty sure the tensile strength ratings are at or close to the breaking point, so the actual "tensional force" or "clamping force" you get at the recommended torque is significantly less than the tensile strength rating of the stud (, but still significantly more than you'd get with the OEM head bolts).
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bass gt  



Joined: 02 Dec 2004
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PostPosted: Mon Jul 21, 2008 9:41 am    Post subject: Reply with quote

Smoothie,

yes, the applicable torque values depend on the material the studs are made from. There are various "compunds" that ARP supply, and you set the trq value accordingly. So by winding it down tighter wont necessarily be a good thing. However, the values ARP give relate to the studs used in conjunction with their assembly lube. I believe that the values increase if you use normal oil. And from memory, the material these studs are made from, the specs rate the trq value at 86ft/lbs. There is obviously some headromm over this if you use motor oil, which is not as good, and causes the threads to bind a little more than their lube. Hop this helps.

Steve
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