Top end rebuild..
Winching
Joined: Jun 2009
Posts: 692
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I've not heard anyone explain why they are putting studs in these motors. I know it's oddball to have bolts, but what is being claimed by ARP or others as the advantage to studs?
I'm assuming you end up with a "standard" stud/head/washer/nut setup when you're done. What do you do for torque? Same final torque plus angle torque? Something different?
If I can find a clear answer on and advantage, I'll likely go that way on my '02 slipped liner/crack behind #6 motor rebuild.
I'm assuming you end up with a "standard" stud/head/washer/nut setup when you're done. What do you do for torque? Same final torque plus angle torque? Something different?
If I can find a clear answer on and advantage, I'll likely go that way on my '02 slipped liner/crack behind #6 motor rebuild.
Super Moderator
Joined: Nov 2009
Posts: 5,847
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From: Arkansas
I've not heard anyone explain why they are putting studs in these motors. I know it's oddball to have bolts, but what is being claimed by ARP or others as the advantage to studs?
I'm assuming you end up with a "standard" stud/head/washer/nut setup when you're done. What do you do for torque? Same final torque plus angle torque? Something different?
If I can find a clear answer on and advantage, I'll likely go that way on my '02 slipped liner/crack behind #6 motor rebuild.
I'm assuming you end up with a "standard" stud/head/washer/nut setup when you're done. What do you do for torque? Same final torque plus angle torque? Something different?
If I can find a clear answer on and advantage, I'll likely go that way on my '02 slipped liner/crack behind #6 motor rebuild.
Maybe they would reduce the chances of cracking the block because you would increase the clamping force without twisting a threaded fastener into the weak block. you'd just install the stud, and then tighten the nut.
I'd also be interested to know what the method is for torquing them using the studs. Is there a formula used to convert from bolts to studs?
Winching
Joined: Jun 2009
Posts: 692
Likes: 9
What you said makes sense in general. But I also agree with the weak point of the block weakness (right at the end of the head bolts) and I don't see how studs will make any difference in that case.
But the rest makes good sense. I hadn't thought about it that way. I'll just want to be 100% sure there is a known good and well tested torquing method before I'd make that change on my block.
But the rest makes good sense. I hadn't thought about it that way. I'll just want to be 100% sure there is a known good and well tested torquing method before I'd make that change on my block.
Super Moderator
Joined: Nov 2009
Posts: 5,847
Likes: 106
From: Arkansas
It's probably just hopeless
I'm thinking the best plan might be to convert a GEMS block to use the BOSCH crank sensor.... there seem to be less D1 with cracked blocks and slipped liners according to what some of the experts are saying.
Winching
Joined: Oct 2010
Posts: 514
Likes: 5
From: IL
I am in the process of doing a top end rebuild on my daughters 2000 DII. It has about 120,000 and her head gasket had a dry break on cylinder 5 or 6 it was. Sounded like a choochoo... Anyway, Was just going to do a head gasket as before that it was running great. Also replacing the raditor as it had a tiny leak... Well as things always go with these pile's when i tore it apart, apparently the previous owner had neglected oil changes as it was baked on sludged up rockers, covers Etc.. Took the heads and had them done and proceeded to strip everything from the top down. I will be doing ARP studs and ceramic coating the manifolds. If any of you need or want pics of any of my rebuild speak now, as i just finished painting all the parts from the block up and will be reassembling later this week. I found a great way to de rust all the manifold bolts as well as some other stuff so let me know what you are intrested in. I may even drop the pan and change the timing cover if i feel in the mood....I hope not....... What a chore.....
Chris
Chris
Please describe the process for installing studs and were these head or main studs? I'm in the middle of a build on a 4.6 and would entertain the installation of studs vs. the head stretch bolts, the mains are not stretch bolts.
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Recovery Vehicle
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today i think
Baja
Joined: Feb 2011
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From: Boston Strong
head stud vs head bolt
One of the main differences between head bolts and head studs involves the methods used to put together or repair an engine. Higher-end head studs that have been specially designed within exact tolerances are capable of securely positioning the head gasket and cylinders with near-perfect alignment. This feature makes it easier to assemble an engine using head studs. However, head bolts are far more convenient for disassembling an automobile engine or for performing maintenance, such as part replacement. Many everyday-use vehicles have master cylinders or other components that extend into the engine compartment. Under these specifications, head bolts allow the cylinders to be removed without removing the entire engine from the car, as is necessary with head studs.
In other words, head studs are better suited for high-performance vehicles with greater power requirements, while head bolts are more practical for personal, everyday automobiles. Therefore, it would be inaccurate to conclude that one type of fastener is categorically superior to the other. Rather, the preference depends on the automobile in question and the ways in which it will be put to use.
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.
In other words, head studs are better suited for high-performance vehicles with greater power requirements, while head bolts are more practical for personal, everyday automobiles. Therefore, it would be inaccurate to conclude that one type of fastener is categorically superior to the other. Rather, the preference depends on the automobile in question and the ways in which it will be put to use.
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.
Thread Starter
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Recovery Vehicle
Joined: Jun 2009
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Likes: 8
yep
One of the main differences between head bolts and head studs involves the methods used to put together or repair an engine. Higher-end head studs that have been specially designed within exact tolerances are capable of securely positioning the head gasket and cylinders with near-perfect alignment. This feature makes it easier to assemble an engine using head studs. However, head bolts are far more convenient for disassembling an automobile engine or for performing maintenance, such as part replacement. Many everyday-use vehicles have master cylinders or other components that extend into the engine compartment. Under these specifications, head bolts allow the cylinders to be removed without removing the entire engine from the car, as is necessary with head studs.
In other words, head studs are better suited for high-performance vehicles with greater power requirements, while head bolts are more practical for personal, everyday automobiles. Therefore, it would be inaccurate to conclude that one type of fastener is categorically superior to the other. Rather, the preference depends on the automobile in question and the ways in which it will be put to use.
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.
In other words, head studs are better suited for high-performance vehicles with greater power requirements, while head bolts are more practical for personal, everyday automobiles. Therefore, it would be inaccurate to conclude that one type of fastener is categorically superior to the other. Rather, the preference depends on the automobile in question and the ways in which it will be put to use.
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.
Winching
Joined: Jun 2009
Posts: 692
Likes: 9
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.
Is that enough to take care of the poor block castings in D2 motors? Who knows. But it definitely can't hurt.
And I never thought about the space thing - I'm used to motors that are so packed in it's easier to pull them to do gaskets, or cavernous engine bays like on the D2s. I've never been too shy about yanking a motor out if I'm doing more than a couple of things at a time to it.
