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Seems like a saw a post about head studs for around 175-200 range would hold 70 psi done some research and caint find it any help
 

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I'm not to sure about that cheap unless they were in the classifieds
 

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I got my ARP's on sale for 380 back in summer of 2010...

if you have patience...wait for the sales... best time to buy.
 

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I got my ARP's on sale for 380 back in summer of 2010...

if you have patience...wait for the sales... best time to buy.
:agree2: Wait for holidays.
 

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Price shopping is like putting the money it would cost for the good parts off till later... When you need to repair what went wrong then buy the good parts. Buy more than what you need and minimalize your chances of breakage


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Are those might diesel head bolts really any better than a stock head bolt?
 

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You do know that manifold pressure is negligible in terms of rating head bolts/studs right?
I think that he was referring to the website saying that some customers report up having no issues even with boost pressures up to 70 psi, So whatever that equals in cylinder pressure. I know that isn't a finite equation, but it gives a round about number to look at.

It looks like they are better than stock, but not as good as ARP. From reading yesterday it seems like they will hold 75% to 80% as much as ARP stuff. For the guys out there running stock turbo maybe a little more this would be a good choice. I myself never plan on getting my truck to the point of needing ARP stuff, but knowing that for $135 bucks I can have something to replace the stock bolts and do a better job seems like a good deal. I myself don't like the idea of retorqueing headbolts since they are supposed to stretch when you install them. I could spend that extra $200 on a vb rebuild or part of a tc, or even just maintenance.

But all of this is relying on if the info out there on these bolts is true.

Here is the thread I read the info on

http://www.cumminsforum.com/forum/94-98-performance-parts-discussion/344262-mighty-diesel-cylender-head-bolts-anything-good-bout-em.html
 

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The same 12.9 bolts can be sourced at Fastenal, except Fastenal will only sell in bulk of like 200 or something. So, if you did buy them in bulk, it would cost about as much as studs will. I'm willing to bet Mighty buys them in bulk and resells them.
 

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That's very likely, any of us could do that same haha, but spending the time to do so isn't something that most of us would do.

Still being 12.9 they should be stronger than stock by a good bit and at the price they are at it makes it a good buy, again assuming what we think is true actually is.
 

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anyone ever consider the difference in clamping forces between studs and bolts?

( I stole this)

Torque Efficiency

During engine assembly or maintenance, a bolt must be installed by torqueing it into place. Due to the head bolt’s design, it has to be rotated into its slot in order to engage the threads and secure it into place. This process creates both twisting force and a vertical clamping force, which means that when the cylinders within the engine’s combustion chamber begin accumulating load, the bolt will both stretch and twist. Because the bolt has to react to two different forces simultaneously, its capacity to secure the head is slightly reduced and it forms a less reliable seal in high-powered engines.
By contrast, a head stud can be tightened into place without any direct clamping force applied through the tightening. A stud can be threaded into a slot up to “finger tightness,” or the degree to which it would be tightened by hand. Afterward, the cylinder head is installed and a nut is torqued into place against the stud. The nut torque provides the clamping force, rather than the torque of the fastener itself, and the rotational force is avoided entirely. Because the stud is torqued from a relaxed state, the pressure from the nut will make it stretch only along the vertical axis without a concurrent twisting load. The result is a more evenly distributed and accurate torque load compared to that of the head bolt. This ultimately translates into higher reliability and a lower chance of head gasket failure.


(Also stolen)

it has to do with the fact that when you torque a bolt into the parent material (be it a head, an engine block, or whatever else) you're fighting against radial flex of the bolt shaft as it gets tighter. The more torque that's applied to a bolt head, the more it will tend to exhibit this radial flex in the shank or shaft area of the bolt in addition to linear stretching. But it's the linear stretch of the bolt that you're attempting to get accurate, and not the twisting flex. The radial flex of the bolt is working against the linear stretch as you're applying torque to it.

And as soon as you let off on the torque wrench, the radial bolt flex will recede, causing the bolt to return back to it's original shape. Since the radial flexing of the bolt shaft will tend to prevent or delay the linear stretch of the bolt, it will require that you place a greater amount of torque on the bolt head in order to achieve the desired linear stretch. This extra torque requirement places greater stress on the threaded hole of the parent material.

With studs the radial flexing doesn't occur nearly as much, if at all, since it's the nut that is being turned during the torque process, and not the stud itself. And the nut takes much more of the torquing force than the stud shaft does. But since the nut is much shorter than bolt shafts are, it doesn't exhibit nearly as much radial flex (twisting flex) as bolts do. Therefore, with a stud, you have a mechanical advantage that you don't have with bolts. The only thing that's the same with studs as with bolts, is that you still get the linear stretch in the studs that you get with bolts. However, since it's the stretch that you're looking for when you apply the torque in the first place, the linear stretch is a good thing. So with studs, you're getting more of the good, and hardly any of the bad so to speak.
 

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What are your plans for the truck?

I ran my stock bolts with stock gasket to 550hp+ and 24* static timing. I used new stock bolts with my o-ringed head last winter when I replaced my 53 block and made 673hp. It was my daily driver then as well. This year I hope to make 750 plus and I'm finally going with studs. The stock bolts will hold more then what a lot of people give them credit for.
 
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^ but why risk it when you can have 400 dollar easy insurance and get arps
 

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i have a hard time getting bent over 400$ for a couple bolts and some nuts....
 
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