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I did then in the truck and they were not that bad and would do them again in there too..
 

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man I never thought headstuds were so hard to install.

even though it is for a diff motoR I saw MADOG uses 14mm head studs.
is that the standard upgrade for a Cummins or is it oversized ie bored out and re-tapped etc?
 

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iirc, 14mm requires some modifications to head and/or the block to install them.

The issue with ARP vs H-11 is not whether or not you can torque them to 200 foot pounds or whatever. Yes, you can tension load them the same as a set of H-11 studs and they will have equal clamping forces on the head the instant you are done torquing them.

The issue is stud stretch over TIME. The longer they are under a tension load the more they will stretch until they are up against their tensile yield strength. It has to do with elasticity, which H-11 is notorious for having very little of. Ever retorque your exhaust maniflolds after a few days? No gaskets to squish, but they stretched over a few days and you will have a good chance of exhaust leaks if you don't retorque them. So when your cheap but overpriced ARP head studs allow your head gasket to pop, rest assured that they didn't maintain clamping forces like H-11 studs would have.
 

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[ QUOTE ]

Not picking on you just because of your IC post.
It just really bothers me when bad info is posted on forums, especially when lack of knowledge is behind them.

H-11's are spec'd @ 120lbs (I torque them to 140)
So are ARP's. (I will be doing the same 140 in Snow White)
At the 120lbs with the same lube both offer the same clamping force.
I have not found out yet the problem in the incorrect torque specs but seems as though they were sent a set of studs and asked to copy them with no real testing done like there was when I originally had A1 make H11 studs for me.

They will both work if torqued correctly.

[/ QUOTE ]

Well...I'm still waiting for you to support your claim, that ARP' and A1's will work the same, with some sort of test data. You have run them both, right?

As it stands right now, the info in my original post isn't looking that bad and my my knowledge isn't quite as lacking as you claim.

Do you have hard data to support what you have posted?

Thanks
 

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[ QUOTE ]
[ QUOTE ]

Not picking on you just because of your IC post.
It just really bothers me when bad info is posted on forums, especially when lack of knowledge is behind them.

H-11's are spec'd @ 120lbs (I torque them to 140)
So are ARP's. (I will be doing the same 140 in Snow White)
At the 120lbs with the same lube both offer the same clamping force.
I have not found out yet the problem in the incorrect torque specs but seems as though they were sent a set of studs and asked to copy them with no real testing done like there was when I originally had A1 make H11 studs for me.

They will both work if torqued correctly.

[/ QUOTE ]

Well...I'm still waiting for you to support your claim, that ARP' and A1's will work the same, with some sort of test data. You have run them both, right?

As it stands right now, the info in my original post isn't looking that bad and my my knowledge isn't quite as lacking as you claim.

Do you have hard data to support what you have posted?

Thanks

[/ QUOTE ]
My apologies, your right I'm wrong.
Carry on.
 

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I did mine in the truck at home. At the same time I changed injectors and put on the h2e. It isn't a terrible job, and you shouldn't have to cut any holes in the floor. It WILL take a good amount of time, so be prepared. I got the whole job done in a weekend, and have some pix of the mods needed for the passenger side, so pm me if you want to see what to do with the A/C box, it should need some trimming. Just a quick word to the wise, buy or rent a porta power to move the engine away from the firewall on the driver's side. (It IS the hardest to do.)
 

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There are no modifications needed to anything to do them in the truck.
Plow look around my web site and get my phone number. Call me and I'll tell you how I did it. If I don't answer leave a message and I'll call you back.
 

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Is there no one that can tell you what amount of stretch you should be putting on these bolts? I know on rod bolts, the most accurate way to tighten them is by measuring rod bolt stretch. A given bolt, of a given material, in a particular size should be tightened till its stretched a pre-determined amount. If you go past this point it will not have ANY clamping load. We had a company come in at work and demonstrate clamping force to us. With a clamp force gauge they would
tighten the bolt to a certain tq. At that tq it had ..say 65,000 psi clamping force.You can loosen and retighten many times and its returns to original size. Once tightened past the yield strength the load goes to 0, or pretty close. And no matter how much its tightened after that it stays at 0. So, if you tighten a fastener past its yield strength, you basically just ruined a high dollar bolt, or in this case stud!

So, my question is..Isnt there someone ( hate to say this...) an engineer with the fastener company........whew... that knows what amount of stretch is right??

Might be some good info to have. Thats why they have tq specs in the first place. Of course I know they have to build in a safety factor too, so maybe if they say 125, it really means 140....lol
 

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[ QUOTE ]
If you want to do them in the truck just use a rubber.
band I mean. Use a rubber band.

[/ QUOTE ]

That's all well and fine if your pulling the heads. I'm talking one at a time.
 

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Some small firewall modifications make it easier with the engine and cab installed.

-Michael
 

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[ QUOTE ]
My apologies, your right I'm wrong.
Carry on.

[/ QUOTE ]

And David sits back and takes a sip of his seventh pink drink! /ubbthreads/images/graemlins/grin.gif
 

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[ QUOTE ]
I got this from another site. Cummins studs, not PSD. Good reading.

[ QUOTE ]
ARP head studs revisted

--------------------------------------------------------------------------------

I got my block back from the machine shop right after I returned from Muncie. I took a copper gasket, the ARP head studs, and a cylinder head and started to check the durabilty of the ARP studs VS TQ applied with a super accurate 1400 dollar TQ wrench I got last winter.

The purpose of this was to check the total amount of TQ I could apply to the ARP studs and not permanently deform them. The idea was to come up with the highest yield I could get before I exceeded the fasteners abilty to continue to apply clamp load and not deform.

The results were very good and I will tell ya the ARP-2000 material is a very ductile and very strong!

ARP has recommended a total TQ of 96 ft lbs using their Moly based lube or 122 ft lbs using 30 wt oil. This according to ARP provided 75% of total yield. Roughly of course. I found out some interesting results while going higher.

First I measured the studs with a micrometer that is accurate to 40 millionths of inch. This was to determine the stretch of the studs after they were TQ'd and removed.

I went to 105 ft lbs and found zero stretch on any of the 26 studs. Then I went to 110 with the same results. I continued torquing, removing and measuring until I got to 151 ft lbs and found 1 stud of the 26 had moved under .001 or 1 thou.

I then proceeded to 160 ft lbs and most of them had moved about 2 thou permanantly. For grins I went to 170 and then to 188 ft lbs were most of the studs were now permanantly moved about .006! I am betting from the way the fasteners felt that I could have gone to 200 ft lbs, but I had concerns of possibly tearing the threads up in the block or deforming them and plus I was just plain tired from torquing those things so many times.

To keep things consistant I washed the studs, washers and nuts in my ultrasonic cleaner between changes to avoid any contamination of small dirt particles, etc. I applied a liberal amount of ARP lube to all the surfaces each time and the temperature was keep constant. The fasteners were allowed to cool between measurements to avoid any heating giving me a false or stretched reading that was not accurate.

I am still amazed at the ability of the ARP studs to take that kind of abuse and stretch this little. That is a super ductile fastener that will do that.

ARP still recommneds officially the 75% yield at 96 ft lbs is best, but says the fasteners should not deform up to 122ft lbs using their moly lube. I found out they can take a little more than that. I guess they have a safety factor built in.

At 125 ft lbs I measured zero permanent stretch! This was after they were TQ'd and retorqed 5 times previous. This is awesome performance. Usually you will break a stud made from 4340 steel at anywhere from 135 ft lbs and up. The ARP went to 188 and only moved .006. That is one tough stud.

To the guys that have purchased the studs from me, I can now say the ARP's are good to 125 ft lbs with ease. The clamp load difference between the ARP recommended 96 and 125 is just over 25% more not counting friction losses.

For a stud that is over 6" in length, .006 thou is not much at all

Don~

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[/ QUOTE ]

That's interesting info for Cummins owners, but for the 7.3 crowd it raises the questions of what size of studs he was testing and whether or not they are of the exact same alloy and heat treat range as ARP's powerstroke studs.
 

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[ QUOTE ]

So, my question is..Isnt there someone ( hate to say this...) an engineer with the fastener company........whew... that knows what amount of stretch is right??



[/ QUOTE ]
Figure it out yourself it isn't too hard. Find a stress/strain curve for the material you are looking for (or just use a generic steel one)http://www.key-to-steel.com/Articles/Art43.htm
Your "clamping force" as you call it is the stress, and the "Strech" of the bolt is the strain. You wan to stay in the part of the graph that looks like a straight line on the left hand side. If you get to the right of that point you permanantly yield the material and the bolt is ruined.
 

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[ QUOTE ]
I can tell you that when you exceed a certain power(pressure) level, even A1's can't hold-and the heads will lift.

[/ QUOTE ]
BB
I have to disagree with you on that statement.
If your power is controlled correctly meaning cylinder pressures are controlled you should not be popping fire rings.
Uncontrolled detonation will break parts and lift heads.
I have been running stock headgaskets with no issues unless we have a problem with the NOS and CP's go thru the roof or in our case through the cylinder walls.
Might need to check out your combonation.
 

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[ QUOTE ]
[ QUOTE ]
I can tell you that when you exceed a certain power(pressure) level, even A1's can't hold-and the heads will lift.

[/ QUOTE ]
BB
I have to disagree with you on that statement.
If your power is controlled correctly meaning cylinder pressures are controlled you should not be popping fire rings.
Uncontrolled detonation will break parts and lift heads.
I have been running stock headgaskets with no issues unless we have a problem with the NOS and CP's go thru the roof or in our case through the cylinder walls.
Might need to check out your combonation.

[/ QUOTE ]

FYI

The fire rings were fully intact, and total timing was 10 degrees. CP's were less than stock, and the gasket was breached on both heads.

Stick to lean conditions and NOS.
 

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seeing that you have no experience with fire rings, you probaly shouldnt be commenting. but since i do, i will. what bb encountered was having only the heads o-ringed. WOP recommends/suggests than in any application where over 80psi will be seen, that the .030 be split between the head and the block, meaning .015 on the block and .015 on the head, creating a well for the rings to sit in. now you know captain lean machine..
 

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Whatever fire ring experts.

If the CP's were less than stock, how do you know what power (pressure) they will let go at? Also, if your CP's are less than stock, *** do you need fire rings for? BOOOOOSHT?

Somethings not adding up here.
 

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until you actually own something that remotely makes power you cant talk. you have no dog in this hunt teletubby.
 
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