Jaryd
Extremely Deplorable
Great info Will. Keep sharing if you want to. Just like Nate I’ll be reading all of this several times again just to make sure I didn’t miss anything and make sure that I take it all in.
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ARP main stud instructions
- Thread starter Will L.
- Start date
Will L.
Well-Known Member
About the the holes being smaller sized,
My knowledge of metal work is limited. But the more you work any metal the worse the hardening and brittleness gets. So if you have a simple drill bit that has a depth stop, like a drill press pre adjusted for instance, so you could take out that material in one pass- you may have no ill affects of added brittleness.
But look how small the amount to remove is. Less than 0.010 . If someone has never tried drilling a sliver of material like that in deep material- what happens is the drill bit tends to go in like a cork screw into a cork plug if at all. Then the edge of the bit actually gets wiped out. Most often the little corner tips of the drill bit just instantly dulls and it never penetrates.
So a cut like this gets done on a bridge port mill or similar with a carbide edge to enlarge the hole, which is where the work hardening happens. The engine builder and the machinist that I was speaking to a out this are the old school guys that learned the best way is the only way mentality. But I can’t help but think there has to be another option.
Simple constant flow of cold water and using a tiny sand paper type flapper wheel or roll paper wheel like used for head porting. Maybe work it for 15 seconds a hole then move to the next one. Then a rest period before doing them all again?
The engine builder friend pointed out the known cracking main web issues and asked a question- any difference in the tiny amount of metal and them not cracking?
Coincidence I am sure, but 2 of the larger hole blocks did crack, 1 GM and 1 GEP. While the 6.2, a GM 6.5 and my GEP none a cracked and won’t fit the studs. But after 3 minutes talking about it, all 3 of us agreed there is no way an additional sliver of material, 0.001 in some holes, could help anything.
We really think it is just simple tool wear on the assembly line or slight variation in bit diameter that makes the difference in if they fit or not.
Look at the tolerance ARP has in the final OD (outside dimension) of shank. A 0.002 range fo both 10mm and 12mm. The 12mm for instance is 0.469-0.471.
And the range of clearances in my block alone for
My 12mm holes:
Front driver 0.468 0.467 0.470 0.467 0.465
Front passenger 0.470 0.465 0.472 0464 0.469
(Hope those stay lined up like I typed them)
Notice passenger side cap 3. If I had screwed a stud in that one first, it would have fit all the way in barely.
But what happens when the block heats up faster than the stud? That .001 will close in and hold the edges of the stud transferring the vibrational load to the danger zone for cracking! All the cap walking forces would be amplified right there. And mainweb 3!?! The most crank and block flex right there. So the one spot I could “help” with a stud could turn to the worst possible scenario and increase the chances of cracking as pointed out to me by the engine builder.
So how big a hole? I don't know. Need to learn.
Give or take, 0.480- 0.490 is the range In the other blocks. 0.010 - 0.020. So we know not to remove excess material in any hole is best. There is a growth rate for cast, so I need to find the chart- I could swear I remember seeing one on a wall poster at a place I worked back in the day.
I also want to verify or dispell my thought of hole finishing. I was thinking because this is such a crack prone area, I know when chamfering the tip of the hole, you do it with a large drill bit, chamfer bit, counter sink bit, etc. then use some emery cloth coned around your fingertip and a quick polish to it afterwards.
So when enlarging holes should I “finish it” with emery cloth or fine sandpaper to remove scratching? It is the rough and sharp edges that you always remove for helping eliminate cracking anywhere.
The conversation with the other guys, machinist and builder, when I got into “what if I open the holes” they just shut down. I know them well enough it is their personality that does it. So I get no where with them on this line. When I ask, well what is the best way to finish a hole for not cracking the response was- “Just smash it with a sledgehammer, you aren’t doing it right anyways!”
Both of their opinion is its a wrong engine in a wrong truck anyways - they both suck. Buy a Honda and move on. So here is where I am stuck and asking for knowledge from everyone out there.
I can’t help but think there is an intelligent, affordable way to open the holes and clear the studs shanks. Not just for me right now, but everyone else that builds afterwards. If we determine that say 0.012 clearance is needed then a simple measure your studs, measure your holes and match up is good. And maybe make a roll sander of emery cloth or 600 grit paper or Something and spend 5 minutes a hole to help a little bit more to fight cracking.
Theories or charts anyone?
My knowledge of metal work is limited. But the more you work any metal the worse the hardening and brittleness gets. So if you have a simple drill bit that has a depth stop, like a drill press pre adjusted for instance, so you could take out that material in one pass- you may have no ill affects of added brittleness.
But look how small the amount to remove is. Less than 0.010 . If someone has never tried drilling a sliver of material like that in deep material- what happens is the drill bit tends to go in like a cork screw into a cork plug if at all. Then the edge of the bit actually gets wiped out. Most often the little corner tips of the drill bit just instantly dulls and it never penetrates.
So a cut like this gets done on a bridge port mill or similar with a carbide edge to enlarge the hole, which is where the work hardening happens. The engine builder and the machinist that I was speaking to a out this are the old school guys that learned the best way is the only way mentality. But I can’t help but think there has to be another option.
Simple constant flow of cold water and using a tiny sand paper type flapper wheel or roll paper wheel like used for head porting. Maybe work it for 15 seconds a hole then move to the next one. Then a rest period before doing them all again?
The engine builder friend pointed out the known cracking main web issues and asked a question- any difference in the tiny amount of metal and them not cracking?
Coincidence I am sure, but 2 of the larger hole blocks did crack, 1 GM and 1 GEP. While the 6.2, a GM 6.5 and my GEP none a cracked and won’t fit the studs. But after 3 minutes talking about it, all 3 of us agreed there is no way an additional sliver of material, 0.001 in some holes, could help anything.
We really think it is just simple tool wear on the assembly line or slight variation in bit diameter that makes the difference in if they fit or not.
Look at the tolerance ARP has in the final OD (outside dimension) of shank. A 0.002 range fo both 10mm and 12mm. The 12mm for instance is 0.469-0.471.
And the range of clearances in my block alone for
My 12mm holes:
Front driver 0.468 0.467 0.470 0.467 0.465
Front passenger 0.470 0.465 0.472 0464 0.469
(Hope those stay lined up like I typed them)
Notice passenger side cap 3. If I had screwed a stud in that one first, it would have fit all the way in barely.
But what happens when the block heats up faster than the stud? That .001 will close in and hold the edges of the stud transferring the vibrational load to the danger zone for cracking! All the cap walking forces would be amplified right there. And mainweb 3!?! The most crank and block flex right there. So the one spot I could “help” with a stud could turn to the worst possible scenario and increase the chances of cracking as pointed out to me by the engine builder.
So how big a hole? I don't know. Need to learn.
Give or take, 0.480- 0.490 is the range In the other blocks. 0.010 - 0.020. So we know not to remove excess material in any hole is best. There is a growth rate for cast, so I need to find the chart- I could swear I remember seeing one on a wall poster at a place I worked back in the day.
I also want to verify or dispell my thought of hole finishing. I was thinking because this is such a crack prone area, I know when chamfering the tip of the hole, you do it with a large drill bit, chamfer bit, counter sink bit, etc. then use some emery cloth coned around your fingertip and a quick polish to it afterwards.
So when enlarging holes should I “finish it” with emery cloth or fine sandpaper to remove scratching? It is the rough and sharp edges that you always remove for helping eliminate cracking anywhere.
The conversation with the other guys, machinist and builder, when I got into “what if I open the holes” they just shut down. I know them well enough it is their personality that does it. So I get no where with them on this line. When I ask, well what is the best way to finish a hole for not cracking the response was- “Just smash it with a sledgehammer, you aren’t doing it right anyways!”
Both of their opinion is its a wrong engine in a wrong truck anyways - they both suck. Buy a Honda and move on. So here is where I am stuck and asking for knowledge from everyone out there.
I can’t help but think there is an intelligent, affordable way to open the holes and clear the studs shanks. Not just for me right now, but everyone else that builds afterwards. If we determine that say 0.012 clearance is needed then a simple measure your studs, measure your holes and match up is good. And maybe make a roll sander of emery cloth or 600 grit paper or Something and spend 5 minutes a hole to help a little bit more to fight cracking.
Theories or charts anyone?
n8in8or
I never met a project I didn’t like
That sounds about right for machinists - in my experience they tend to be very binary.....there’s only one way to do something and that’s 100% without any wiggle. That’s great and admirable, but that doesn’t fit everyone’s budget. You need to have a somewhat open mind and be able come up with alternate approaches to a problem sometimes so a good result with a reasonable outlay of labor and cost.
Maybe this is a dumb idea, but I’ll ask anyway. You said the correct order of operations for the cryo treatment was to have the cryo done and then machine after, right? What if the main bolt holes were done pre-cryo and then all other machine was done post-cryo? Could the cryo treatment take care of any adverse metallurgical affects that happen from enlarging those bolt holes? Just a thought. Or maybe there would be a way to anneal the metal after? I didn’t get far into properties of materials in school unfortunately.
Maybe this is a dumb idea, but I’ll ask anyway. You said the correct order of operations for the cryo treatment was to have the cryo done and then machine after, right? What if the main bolt holes were done pre-cryo and then all other machine was done post-cryo? Could the cryo treatment take care of any adverse metallurgical affects that happen from enlarging those bolt holes? Just a thought. Or maybe there would be a way to anneal the metal after? I didn’t get far into properties of materials in school unfortunately.
ak diesel driver
6.5 driver
They make reamers for getting holes to exact size, that's what I'd be using. Drill bits are not that exacting plus chips can gall the hole so usually you drill or bore a hole and then use a reamer
I agree with Les, a reamer and say a magnetic drill at a set depth would be a way to do it if folks don't have access to a big mill that would handle a block, and if a machine shop is willing to do that much think about going a bit deeper with the holes and threads.... then have it cryo treated to stabilize everything..
Will L.
Well-Known Member
On the chryo first thing- no because chryo makes it take more time and more force to wear the metal. This is opposite of what’s desired to elevate brittleness.
A reamer is a great idea. Where is my MSC catalog? Haha. There should be a speed and feed rate for the material and amount coming out. Just need to determine what the optimum size would be. Need to find the expansion chart.
I also thought about going deeper with threads.
But the holes are over the cut outs for the pistons. I think they drilled them about as deep as you can go.
Something engine builders learn know to do that diy folks may not like chamfering is equalizing the thread depth for stud. Basically in running your thread chaser- not tap- you count the revolutions or amount of threads as you go and write them down. Find the deepest one and cut threads (tap) in the others to match the deepest setting.
This has controversy because maybe the engineers left holes x,y &z more shallow because they know of issues. But you’ll find most are random with experience of doing 25 or more engines and seeing no failures come from it.
From the boat loads of 6.5s I’ve done- I already ran bread chaser, tap, then chaser again down mine in prep for the studs. The difference of 1/2 or even1 more thread doesn’t matter with bolts. Also this is done with a high quality tap you dull the sides on past the 3rd new thread as to not have extra cutting in you other threads above. My GEP had 1 hole that went an extra190-200 degrees. Most were within 1/4 turn or 90 degrees.
On the depth of drilling- the off the shelf studs in the kit almost completely maximize thread strength by length. So custom studs with more threads is helpful to get past the smaller holes, but don’t add more threads that would contribute to holding power. So more material intact inthe main web is probably more valuable.
A reamer is a great idea. Where is my MSC catalog? Haha. There should be a speed and feed rate for the material and amount coming out. Just need to determine what the optimum size would be. Need to find the expansion chart.
I also thought about going deeper with threads.
But the holes are over the cut outs for the pistons. I think they drilled them about as deep as you can go.
Something engine builders learn know to do that diy folks may not like chamfering is equalizing the thread depth for stud. Basically in running your thread chaser- not tap- you count the revolutions or amount of threads as you go and write them down. Find the deepest one and cut threads (tap) in the others to match the deepest setting.
This has controversy because maybe the engineers left holes x,y &z more shallow because they know of issues. But you’ll find most are random with experience of doing 25 or more engines and seeing no failures come from it.
From the boat loads of 6.5s I’ve done- I already ran bread chaser, tap, then chaser again down mine in prep for the studs. The difference of 1/2 or even1 more thread doesn’t matter with bolts. Also this is done with a high quality tap you dull the sides on past the 3rd new thread as to not have extra cutting in you other threads above. My GEP had 1 hole that went an extra190-200 degrees. Most were within 1/4 turn or 90 degrees.
On the depth of drilling- the off the shelf studs in the kit almost completely maximize thread strength by length. So custom studs with more threads is helpful to get past the smaller holes, but don’t add more threads that would contribute to holding power. So more material intact inthe main web is probably more valuable.
ak diesel driver
6.5 driver
So my question is would it be appropriate to use lock tight when you put the studs in and that would allow you to set the shoulder at the appropriate height and then not worry about them shifting?
Will L.
Well-Known Member
The loctite is good, but you are supposed to do it on assembly.
Something old racer trick for soft bottom end was to mix heat ajb weld, then use it like thread locker. It surely held. I did a couple engines that way. But long term: jb weld expands and contracts at a different rate than the metal, so thats ok for the track, not for an engine you want to go 1/2 million miles.
Something old racer trick for soft bottom end was to mix heat ajb weld, then use it like thread locker. It surely held. I did a couple engines that way. But long term: jb weld expands and contracts at a different rate than the metal, so thats ok for the track, not for an engine you want to go 1/2 million miles.
ak diesel driver
6.5 driver
so if you wanted to do that you'd assemble it with the locktight and after it sets up you could pull the caps off without anything shifting?
Will L.
Well-Known Member
No. Loctite is to stop vibration, not to sieze the bolt or stud solid from moving. The forces of removing nut and allowing released tension of the threads would negate the loctite.
Does the loctite hold it there still, yes. But not solid like you can disassemble and reassemble it afterwards.
This is for regular loctite. There may be a specific one they make that does sieze it totally. But note en fed max strength loctite that you apply heat to break free is rated for that.
Thats why someone came up with the jb weld thing.
Does the loctite hold it there still, yes. But not solid like you can disassemble and reassemble it afterwards.
This is for regular loctite. There may be a specific one they make that does sieze it totally. But note en fed max strength loctite that you apply heat to break free is rated for that.
Thats why someone came up with the jb weld thing.
Will L.
Well-Known Member
I had 2 people ask me about getting studs to the bottom of the holes. There are 3 styles of taps, and 3 variations of each. Somewhere out there is probably a great instruction sheet that teaches which is which and what they do. I don’t have one, I just know the differences. You have taper, plug, & bottom taps. A taper tap you lose the fist 8 threads, a plug is 4 or 5 lost, and bottom looses 2. Most tap and die kits people buy is taper because you need it to self center easy. I never buy plug taps- only machinist really use them.
I mentioned a person could hack a straight cut bottoming tap to do it with, but I probably shouldn’t have said that. It is easy to screw that up and create problems. Best is to buy the right tap to do it with, get a bottoming tap that’s spiral flute. Spiral is to push the cut metal up out the hole. Straight taps are far more common but half the shavings come out and half go down the hole. A straight tap is much stronger, but you can bind from the metal shavings in the hole.
Some guys buy straight cut taps and just run the tap in and out a couple extra times to clear all the waste. Others learn how to take out a couple threads and get away with it (guilty).
But if you have to buy a bottoming tap anyways- get the spiral and go easy on the pressure. The more times you run a tap in and out the hole, the worse your threads end up.
Black oxide is fine and dandy for cast iron. The shiney taps are a finish for things that bind and gaul like stainless steel or aluminum, so save $ or spend more based on what else you may or may not use them on.
I was a MAC TOOLS distributor for a minute or two. Something Mac does no one else I know of does is lifetime warranty on drillbits, tap & die, carbide burrs, rotor broach and probably a few more related tools I can’t think of off hand. And no tool guy near you is no biggie because 1 800 mac tool for buying and warranty. They have website also but their website sux. So I normally recommend checking with them first, But I can’t remember ever having ordered any. Some people get bottoming taps free with some wear on them from machinists because they break easier, so they dont run them if there is any time on them to speak of. Wish I could get freebies! No dice.
I mentioned a person could hack a straight cut bottoming tap to do it with, but I probably shouldn’t have said that. It is easy to screw that up and create problems. Best is to buy the right tap to do it with, get a bottoming tap that’s spiral flute. Spiral is to push the cut metal up out the hole. Straight taps are far more common but half the shavings come out and half go down the hole. A straight tap is much stronger, but you can bind from the metal shavings in the hole.
Some guys buy straight cut taps and just run the tap in and out a couple extra times to clear all the waste. Others learn how to take out a couple threads and get away with it (guilty).
But if you have to buy a bottoming tap anyways- get the spiral and go easy on the pressure. The more times you run a tap in and out the hole, the worse your threads end up.
Black oxide is fine and dandy for cast iron. The shiney taps are a finish for things that bind and gaul like stainless steel or aluminum, so save $ or spend more based on what else you may or may not use them on.
I was a MAC TOOLS distributor for a minute or two. Something Mac does no one else I know of does is lifetime warranty on drillbits, tap & die, carbide burrs, rotor broach and probably a few more related tools I can’t think of off hand. And no tool guy near you is no biggie because 1 800 mac tool for buying and warranty. They have website also but their website sux. So I normally recommend checking with them first, But I can’t remember ever having ordered any. Some people get bottoming taps free with some wear on them from machinists because they break easier, so they dont run them if there is any time on them to speak of. Wish I could get freebies! No dice.
ak diesel driver
6.5 driver
There's also different materials they're made from. Machinist buddy of mine told me to buy HSS for a good quality tap. Since then the Chinese ones have come out so make sure you get good quality ones when it really counts
Will....why don't you leave your block alone and have ARP build the 6.5 mains kit with a few thou milled off the shank before the threads are cut and the stud hardened? The bolts are in tension and along the Z axis they are the strongest and a few thou will have little impact on the plastic deformation. the bolt will be de-rated but the advantage of the stud vs. TTY will be there.
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Will L.
Well-Known Member
That is something I am considering. I have quotes back on a couple variations of custom studs from them. The prices range from 58-74 dollars per stud. After shipping and tax looking at around $1,500 for a set. Still chasing other options, but building these engines for some other folks, I already ordered and received the 2 reamers to squeak open the hole for that option. The 2 reamers was under $100.
Nothing done right is free...
And welcome to the forum btw.
Nothing done right is free...
And welcome to the forum btw.
Will L.
Well-Known Member
This popped back up in my life, so I will update it.
The 2 reamers I bought worked super easy and perfect.
I had one of the machinists at my house and showing him what I was planning, and was just waiting to borrow a mag drill. After a couple minutes I went inside to get us drinks, and came out to him doing the second hole with my frickin dewalt cordless!! When my panic calmed and he explained it, I did the rest of the holes. They self center like a dream and it is smooth and easy. Set the clutch on the drill low so it would slip if there was binding.
One issue down.
The torque is still my other delay. I can’t afford to have them load cell tested, but a diy load cell will do the same thing. Starting out with what what stud nut torque is equal to the factory bolts is question #1 in figuring this out. I have a couple options that aren’t crazy expensive, wish I still had my portapower.
Anyone have one they wanna play with to determine this?
The 2 reamers I bought worked super easy and perfect.
I had one of the machinists at my house and showing him what I was planning, and was just waiting to borrow a mag drill. After a couple minutes I went inside to get us drinks, and came out to him doing the second hole with my frickin dewalt cordless!! When my panic calmed and he explained it, I did the rest of the holes. They self center like a dream and it is smooth and easy. Set the clutch on the drill low so it would slip if there was binding.
One issue down.
The torque is still my other delay. I can’t afford to have them load cell tested, but a diy load cell will do the same thing. Starting out with what what stud nut torque is equal to the factory bolts is question #1 in figuring this out. I have a couple options that aren’t crazy expensive, wish I still had my portapower.
Anyone have one they wanna play with to determine this?
n8in8or
I never met a project I didn’t like
I've been waiting to see an update to this! I have a porta power and access to a load cell at work. Unfortunately I will be out of town camping for the next few days. If you don't get anyone to help you before I'm back, I'll be your huckleberry.
Will L.
Well-Known Member
So.. Nate and I spoke and the load cell he has at work won’t work for this situation.
Most of us will gain a lot of block security by using studs at or near factory clamping force. Too much clamp force does indeed apply extra stress onto the block main webs. I have in the past said only studs added should not cause damage and have since been shown I was is incorrect. Several hours talking to mechanical engineer and having things in front of us they showed me with ut it is way too hard to explain. In the future I could try posting some articles that touch on it to give the idea but basically the webs and caps clamp on the crank, but that force gets applied tothe main webs in a downward 270° direction. This will amplify the web cracking issue. Using the lower part of the threads will help just like most of us figured. They said it would also help in cap walk even at the same clamp load because of the more stable fastener.
I bought a 10 ton set up and have the gauge for the correct gauge along with most of the the fittings required. Now I need the hallow hydraulic actuator (ram). I will post a video that shows how the clamp load gets measured this way. I am going to post specs on optional actuators incase by any dream of a chance someone here has one I could use for this rather than buying one. I would need it for One day so long as I get dimensions ahead of time and build the two bases required.
When done, I will have torque spec for studs equivalent to factory bolt torques and up to maximum capacity and what the clamp force applied is. I am going to put all info uphere for everyone to use. My hope is the guys selling studs include a comparison sheet with their kits so customers understand all their options and can set torque accordingly down from the old max numbers folks used to use.
Most of us will gain a lot of block security y using studs at or near factory clamping force. Too much clamp force does indeed apply extra stress onto the block main webs. I have in the past said only studs added should not cause damage and have since been shown I was is incorrect. Several hours talking to mechanical engineer and having things in front of us they showed me with is way too hard to explain. In the future I could try posting some articles that touch on it to give the idea but basically the webs and caps clamp on the crank, but that force gets applied tothe main webs in a downward 270° direction. This will amplify the web cracking issue.
I will need to buy 2 new arp studs, one of the 10mm and one of the 12mm along with 2 new main stud bolts, also a 10mm & 12mm. Then buy some cold roll and do some heavy welding to build the stud/ bolt adapter. Might pay a machine shop to turn the pieces needed depending on price. (I sure hate not having access to a machine shop anymore)
I will post the hydraulic actuator soon as I get more free time.
Most of us will gain a lot of block security by using studs at or near factory clamping force. Too much clamp force does indeed apply extra stress onto the block main webs. I have in the past said only studs added should not cause damage and have since been shown I was is incorrect. Several hours talking to mechanical engineer and having things in front of us they showed me with ut it is way too hard to explain. In the future I could try posting some articles that touch on it to give the idea but basically the webs and caps clamp on the crank, but that force gets applied tothe main webs in a downward 270° direction. This will amplify the web cracking issue. Using the lower part of the threads will help just like most of us figured. They said it would also help in cap walk even at the same clamp load because of the more stable fastener.
I bought a 10 ton set up and have the gauge for the correct gauge along with most of the the fittings required. Now I need the hallow hydraulic actuator (ram). I will post a video that shows how the clamp load gets measured this way. I am going to post specs on optional actuators incase by any dream of a chance someone here has one I could use for this rather than buying one. I would need it for One day so long as I get dimensions ahead of time and build the two bases required.
When done, I will have torque spec for studs equivalent to factory bolt torques and up to maximum capacity and what the clamp force applied is. I am going to put all info uphere for everyone to use. My hope is the guys selling studs include a comparison sheet with their kits so customers understand all their options and can set torque accordingly down from the old max numbers folks used to use.
Most of us will gain a lot of block security y using studs at or near factory clamping force. Too much clamp force does indeed apply extra stress onto the block main webs. I have in the past said only studs added should not cause damage and have since been shown I was is incorrect. Several hours talking to mechanical engineer and having things in front of us they showed me with is way too hard to explain. In the future I could try posting some articles that touch on it to give the idea but basically the webs and caps clamp on the crank, but that force gets applied tothe main webs in a downward 270° direction. This will amplify the web cracking issue.
I will need to buy 2 new arp studs, one of the 10mm and one of the 12mm along with 2 new main stud bolts, also a 10mm & 12mm. Then buy some cold roll and do some heavy welding to build the stud/ bolt adapter. Might pay a machine shop to turn the pieces needed depending on price. (I sure hate not having access to a machine shop anymore)
I will post the hydraulic actuator soon as I get more free time.
Time to sue DSG! "These ASSHATS" as Gale Banks would call em. Who knows how many people screwed their blocks trying to make them stronger because of inept product engineering.
The shortest compressed height for a hollow hydraulic cylinder I could find was 51mm (2.008") which is still longer than how far the outer main bolts protrude from the block when fastened (1.83"). Testing at 51mm may add some error due to there being ~10% more bolt sticking out to stretch under load and there being at least 3 fewer threads used when torqued. But an engineer could account for that and calculate a torque spec that isn't DSG levels of overkill.
The shortest compressed height for a hollow hydraulic cylinder I could find was 51mm (2.008") which is still longer than how far the outer main bolts protrude from the block when fastened (1.83"). Testing at 51mm may add some error due to there being ~10% more bolt sticking out to stretch under load and there being at least 3 fewer threads used when torqued. But an engineer could account for that and calculate a torque spec that isn't DSG levels of overkill.
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The link to DSG's main stud girdle torque instructions went stale.
Thanks to wayback machine, it's still on the internet.
Thanks to wayback machine, it's still on the internet.
n8in8or
I never met a project I didn’t like
Have there been block failures reported after DSG girdle installation?