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Old 08-20-2015, 12:31 PM   #26
rustler753
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I called your builder to mention what we have been though. I mentioned he should give my builder a call.
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Old 08-20-2015, 01:10 PM   #27
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Originally Posted by user1029 View Post
Yeah but if you accumulate heat cycles say from driving to work, then going to Applebees with your buddies for lunch (god I hate that place), then go up your date to Golden Corral, then to the movies, then back her place, then I think that is where the 1/2 stud problems arise


Most likely install error



Driving across the United states of america shouldnt lift the head when using 1/2" studs at 21 psi. I'll go ahead and guess A. Install error or B. Tuning issue
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Old 08-20-2015, 01:13 PM   #28
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Originally Posted by vicious_fishes View Post
are ourfront taking responsibility or are they blaming an install error like every other time anything ever goes wrong for anyone? (not that it isn't often the case...)
How could you possibly expect every company to take responsibility for parts they didn't install such as this

I can under stand say a turbo or even a shock... head studs where machining is required and proper torque specs/sequence. Not a chance
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Old 08-20-2015, 03:15 PM   #29
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Originally Posted by wEaK Squad View Post
Most likely install error



Driving across the United states of america shouldnt lift the head when using 1/2" studs at 21 psi. I'll go ahead and guess A. Install error or B. Tuning issue
Agreed, I've seen north of 42psi with no issues. If they were going to pull they would have when I torqued them down 4-5 times during machining and assembly. Did you use any arp lube on the threads and make sure they went in straight? Mine are torqued over 125lbs as well
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Old 08-20-2015, 04:50 PM   #30
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One of the failures was done by outfront themselves. They told the shop that the block was "soft" and shipped them time-serts...
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Old 08-20-2015, 04:54 PM   #31
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Also Killerbmotorsports has their opinions on these studs too:
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I have a problem with the design perspective of the 1/2" studs. The structural integrity will never be good 100% of the time IMO and here's why...

When you tap drill the OEM threads out of the block for 1/2" studs it doesn't remove all of the old threads. If you take a cross section of the block you will see there is still some of the old thread there. Having been a student of fastener technology for some time now, we know that a thread is only as strong as the design and the quality of the manufacturing process. Super high quality threads will have a chamfer (not made after the threads are cut) at the top and ream to clean up any scratches left by the drill point, (although this is at the pinnacle of manufacturing quality and beyond what's necessary here IMO), then there are cut threads and formed threads with the later (like any cold formed or forged part) being much stronger.

So you drill most of the old threads out and now tap 1/2 threads into them. It adds a cross cut through a decent percentage of the threads, significantly reducing their yield strength. Since studs stretch, not all threads are loaded equally so where the compromised threads are dispersed can have a decent impact on overall strength too.

You can calculate thread load and thread engagement as being so much better with 1/2" threads vs OEM, better clamping force, blah blah blah, but all those calculations go out the window because the threads have a built in, and inconsistent, defect. It's impossible to calculate the strength with this defect in place.

So the other option is to oversize the tap drill and remove all the old threads. While this might seem like a good idea for removing the weakness of the block threads, it places the load further out on the face of the stud thread. This in itself has its own issues, none of which are good.

My point here is if you pickup a book on fastener design, most of this stuff goes back nearly 100 years. What you see with these 1/2" threads is a big no-no according to thread design parameters.

ALL THAT being said... the forces involved may be so minor compared to the thread and/or stud capabilities that it may be a moot point... BUT, no one in this industry (that I know of, please share if it's out there!) has any scientific data proving as much. When I say scientific I mean in a lab, by a 3rd party, testing all versions side by side.

IMO two better choices (only from a design and materials standpoint) would be to use a super badass stud like the ARP625 that uses the OEM roll formed threads, or the 14mm studs that completely removes ALL the OEM thread and allows for a full proper thread to be machined. The later has been done with success for over a decade over in Europe.

The 1/2" stud has been gaining popularity in the states, especially over the last several years. Is that due to time tested results, influence from those selling the upgrade, or assumptions (maybe correct ones?) and a push from the end user that bigger is better so me must have it! The other thing is at the power levels we're typically talking about, where these are used, there is definitely going to be a '**** happens' factor. Until someone cuts apart a block that has known failed threads (with repeatability) to determine where the failure point originated from, it's all speculation
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Old 08-20-2015, 05:24 PM   #32
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man this sucks, sorry to read this stuff. I am glad I used my ARP 625+ studs in my OF closed deck, and did not get the 1/2" studs.
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Old 08-20-2015, 05:31 PM   #33
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I had a perfectly good set of l19's i should have kept. Lol
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Old 08-20-2015, 06:54 PM   #34
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Pretty sure it's just install error on the builders part. We have built a couple closed decks with 1/2" studs lately. I can say that it's very hard to clean all the machine shavings from behind the cd plates. That includes the stud holes especially. If there were any shavings or small machining particles that remained in the stud hole it could easily put more of the pressure on certain threads and not distribute the torque out evenly. You should chase each hole with a thread chaser to catch any small particles that remain from the closed deck machining. If you have never seen a 1/2" stud it is huge. The threads are also a lot bigger than the 11mm stud. It would be near impossible to pull the thread in the block unless the stud was not fully seated on the bottom and each thread was against another clean thread.

Now if the hole was not drilled exactly straight into the hole then I could see how you might pull a stud out.
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Old 08-21-2015, 12:35 AM   #35
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I don't buy the install error. There are various shops that have seen this, its not isolated and there was an instance where outfront did one themselves blaming it on the block being soft.
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Old 08-21-2015, 11:34 AM   #36
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I wonder if we will see any of the new IAG closed deck blocks with 1/2" studs pull the threads like this...
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Old 08-21-2015, 06:07 PM   #37
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Lol yea all of them will, happens to every outfront block too
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Old 08-22-2015, 07:21 PM   #38
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What is the reasoning for everybody getting into 1/2 studs now? Just easier to get then 14mm? If 14 is an option why would anyone use 1/2 instead.
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Old 08-22-2015, 07:40 PM   #39
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Originally Posted by linkubus06 View Post
I wonder if we will see any of the new IAG closed deck blocks with 1/2" studs pull the threads like this...
I talked to JJ about the IAG ARP2000 1/2" studs that was a part of their closed deck/O-ring package which CJ make 1000awhp on. JJ told me that IAG has modified their approach for installing 1/2" studs in comparison to Outfront. He postulated that the main overlooked problem is the accumulation of metal shavings at the bottom of the 1/2" stud during installation. This build up of metal shavings acts as an impedance as the stud is advanced further inward to that level. This hindrance results in the deformation of threads as the head studs are torqued down tighter against that resistance.

To work around that, IAG has a machine that sprays coolant as the stud is advanced inward thereby preventing the potential accumulation of metal shavings at the very bottom. This allows for increased atraumatic purchase of the 1/2" stud against the threads as there would be nothing fighting against it.
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Old 08-22-2015, 07:40 PM   #40
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Originally Posted by cowboy_Rob View Post
What is the reasoning for everybody getting into 1/2 studs now? Just easier to get then 14mm? If 14 is an option why would anyone use 1/2 instead.
14mm would require rethreading the block. IAG is working on that
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Old 08-24-2015, 07:23 AM   #41
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Originally Posted by user1029 View Post
I talked to JJ about the IAG ARP2000 1/2" studs that was a part of their closed deck/O-ring package which CJ make 1000awhp on. JJ told me that IAG has modified their approach for installing 1/2" studs in comparison to Outfront. He postulated that the main overlooked problem is the accumulation of metal shavings at the bottom of the 1/2" stud during installation. This build up of metal shavings acts as an impedance as the stud is advanced further inward to that level. This hindrance results in the deformation of threads as the head studs are torqued down tighter against that resistance.

To work around that, IAG has a machine that sprays coolant as the stud is advanced inward thereby preventing the potential accumulation of metal shavings at the very bottom. This allows for increased atraumatic purchase of the 1/2" stud against the threads as there would be nothing fighting against it.
Wow, I told ya'll that was the issue in my last post and it got dismissed. It's install error plain and simple on the part of whoever installed the studs in the block. You guys can stop throwing outfront under the bus.
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Old 08-24-2015, 08:12 PM   #42
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Hey bud! I'm the other "occurrence". My used case that i sent in (701) for closed deck and 1/2 studs pulled on one of the outer holes. They sent my builder a time cert, got that in and put it back together and had another one pull!
Now i had two options... Get a other new case, re machine everything, line hone (arp case bolts). Or time cert every hole. So I'm going with time certs on every one! Very frustrating as ive been waiting months on my build. And into it alot of money.

Go on vacation and come back to an out of control thread : Josh you are not the other "occurrence" you are the only occurence. Let's take a logical approach to the issue of the first studs to pull out. When Josh's builder called us 2 weeks ago about a stud pulling, we let him know that was the first one in over 1500 studs sold that we have seen(and i'm sure we had done the machining to at least 1100 of those studs) we told him that we would send up a new 1/2-13 timesert kit (it's brand new at this point we have never needed to use it) we next day air'd to him and said we would pay the cost of machineing for the one hole. We're assuming that it is possible to have had a mistake in 1100 holes done. When the builder called a few days later he told me that now another hole had pulled. Sorry, but at this point I don't believe that it could be possible to now have two holes bad, let alone in the same block.

At this point other reasons could be that the block is soft. A block can get soft after a super severe overheating. We let the builder know the two options, #1 at our cost the customer could supply another block and we would both closed the deck and tap for 1/2 studs for no charge (over $1000 of labor) , but we get to have the old block for testing purposes, or #2 we could help with the charges of timeserting the block, we actually don't like option #2 because we wouldn't get his original block back for testing. Because this block already had a lot of prep work done to it, it was decided to timesert the block I understand the reasons but leaves no ability for me to do testing. At current there is no way to pre test a block before tapping as the soft issue may not be through the entire block (this is why we would want his block in our hands) If the block is soft, we don't consider that we would be responsible, (this is my assumption at the current time) but because this is the first occurrence we want to help where we can. Because we won't be getting the block back, we will be back at square one and will never know the real cause. I personally tap each block with an assistant on a mill, straight as an arrow, with a counter bore too. After cleaning we have a test stud that is marked and installed to make sure it bottoms in the block.

John, Owner, Outfront Motorsports

Last edited by outfrontmotorsports; 08-24-2015 at 09:17 PM.
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Old 08-24-2015, 08:16 PM   #43
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Originally Posted by rustler753 View Post
That blows even more that you had yet another pull out.

My builder decided to time sert every hole too.

Did outfront do anything money wise to help cover your costs? Seeing how they machined it.
From reading the above post it looks like I was taking care of the issues, as it was the first one we heard of and after all we could have made a mistake. this assistance was pre this thread

Outfront

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Old 08-24-2015, 08:19 PM   #44
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Originally Posted by slide View Post
Wow this sucks. I wonder if the future install will involve some sort of sleeve for the head studs... That would suck...

Or like the old a-series motors, the "s" model they actually installed an additional head stud...
No, this was a one off case and highly unlikely to occur again. If it happens again we will hopefully get the block back, we feel this is a red herring. We still would not recommend to do timeserts to use our studs.

Outfront

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Old 08-24-2015, 08:24 PM   #45
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Originally Posted by user1029 View Post
Yeah but if you accumulate heat cycles say from driving to work, then going to Applebees with your buddies for lunch (god I hate that place), then go up your date to Golden Corral, then to the movies, then back her place, then I think that is where the 1/2 stud problems arise
For clarification: a soft block will not occur by the heat cycles you are talking about. It would only be a super severe overheating. Our 1/2" heads studs are not the issue, if you have issues with your studs (yeah, the ones that look just like the ones we created years ago) you need to go to your builder to find out why

Outfront

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Old 08-24-2015, 08:26 PM   #46
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are ourfront taking responsibility or are they blaming an install error like every other time anything ever goes wrong for anyone? (not that it isn't often the case...)
I suppose this is a generic statement of shops in general? To answer your question, Yes, before this thread was started too. BTW, I never blamed an install error either.

Outfront

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Old 08-24-2015, 08:30 PM   #47
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Originally Posted by DisoDisp View Post
As in the other thread, this is why we use 14mm studs, proper thread engagement. Which is not possible with 1/2" studs.

I remember outfront being very defensive too saying their thread engagement is perfect and noone has ever had issues, much like the closed deck blocks that never fail
Ok DisoDisp, How can I say it again so you don't think I'm defensive? maybe you have sold a few 14mm studs, I have sold 1000's of our 1/2" units. there is no issue, if you would like we can go into detail on the actual engagement details, thread designs and machining tolerances and how you are literally splitting hairs in "your defense"

This also includes the large statement from Killer Bee from the OP, what either one is talking about is completely insignificant to the stud strength. Just a little info would be to have 2.0 x the thread diameter in aluminum for total strength. That would be 1.0 inches of thread engagment, our stud has 3.0 x the thread diameter 1.5" plus an additional .75" of a partial thread that we also take advantage. There are always compromises in everything. we don't prefer the 14mm studs for they are way overkill IMHO, it requires special gaskets, a lot more expensive to tap for the studs than ours. even the dowell needs to be custom or modified to work. If 95% of customers are torqueing their heads to under 140ft/lbs what's the point? We only charge $180 to tap for our studs as we are set up to do this daily, what do you charge to prep a block for your studs? can you include the charges for the dowels and gaskets too?

Outfront

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Old 08-24-2015, 08:31 PM   #48
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Originally Posted by waylouderthanyou View Post
This is troubling, i just had outfront build my shortblock and machine my 703 case halves for 1/2'' headstuds. In for more info.

CAN ANYONE ELABORATE ON HOW ALTITUDE PLAYS INTO THIS?
As noted we stand behind our work!

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Old 08-24-2015, 08:38 PM   #49
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Do the Outfront 1/2" studs use a dog point? If not, does the stud bottom out in the hole or does it bottom out on the shaft of the stud (where the threads end)? How much torque are you applying when installing the studs into the block?]
Yes, Dog Point
No of course not, the holes are couterbored to avoid the threads bottoming out

We tighten them with a speed handle and oil or light grease, there is no reason to use thread lube on this side of the stud, only the head nut side. The torque you ask/ 5-10 ft.lbsBTW the dog point, brand of stud, material, everything really looks like our original stud, imitation is the most sincere form of flattery

Outfront

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Old 08-24-2015, 08:40 PM   #50
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Originally Posted by rustler753 View Post
One of the failures was done by outfront themselves. They told the shop that the block was "soft" and shipped them time-serts...
This was the only one in question, this was Josh's block. We will not know if the block was soft but we are resolving before this thread was started

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