Lucky catch

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Re: Lucky catch

Post  Lem Evans on January 4th 2014, 12:44 pm

Larry T wrote:yes I have had problems with the Lunati and ford brand rockers mostly Lunati.i have started replacing them with the Harland sharp rockers.no problems yet except for some clearancing in the trunnion area were they hit the top edge of the spring.

for the new motor I am building I was considering the comp cams  Next gen Ultra-Gold ARC rockers but the listing on their web page says 351c and dosent say 429/460 as it did earlier.

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=19045-16&Category_Code=

I have had to tare down 3 motors because of the rockers coming apart and I can tell ya it wasn't from the lack of maintenance.if a rocker cant take at least five 1/8th mile hits with out coming apart theirs a problem.

so my question is who makes the better rocker?
 
Larry, if you are going to run a Comp rocker the 1830-16 Ulta Pro Magnum XD is the way to go. They are 8650 steel, lifetime guarantee against breakage and are rebuildable. They are similiar in price to the aluminium but are a lot stronger.

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Re: Lucky catch

Post  Paul Kane on January 4th 2014, 12:53 pm

I think that the Crane and classic Lunati rocker arms are not only adequate but to be considered pretty much middle-of-the-road industry standard for our 385 Series stud rocker arm offerings. Valve trains are pretty elaborate systems that are constanty subjected to repeated, highly stressful, coninuously cycling forces of various kinds. This is why proper valve train geometry is paramount.

For example, poor valve train geometry can lead to premature valve float which may lead the end user to mistakenly think he needs more spring when in fact he really needs to reduce his valve train harmonics by way of further optimizing his valve train geometry. Choosing more spring in a valve train with poor geometry means more unnecessary forces that hurt the valve train and more frictional losses (power loss) from the larger-than-necessary spring pressures, and evenutually a valve train falure. On the other hand, correcting the reason for the valve float via optimizing the geometery reduces unnnecessary forces and improves power without a spring pressure increase.

Properly set up, the Crane and Lunati rockers are fine within their intended applications. That said, engine builds today (and their associated valve train standards) are far more aggressive than when those particular rocker arms were designed, and that's one of the reasons we are seeing more steel roller rocker arm offerings today.  But good quality aluminum in properly engineered and manufactured rocker arms are still very viable in most builds.
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Re: Lucky catch

Post  Paul Kane on January 4th 2014, 12:58 pm

David Cole wrote:...I got bit with the Comp Ultra Golds.   30 passes with the stock supplied TFS A460 springs on a 588.  Close inspection looked like a stress crack started where they pressed the pushrod cup in.   Whole back half of the rocker just snapped off.  



Paul Kane wrote:What few people know about the American rocker arm industry today they would find downright shocking. And I'm not necessarily talking about your point of "offshore," I'm referring to what goes on here on American soil.
There's a deep, "dark secret" reason why that rocker arm failed as it did, and I believe you will have that same experience if you subject another set to a big roller springed engine as the first set was. Same with a scorpion. I'll never run a scorp or comp gold on a big roller springed engine; I think it's like asking for trouble. Frankly, I don't think they should be allowed to be advertised/sold as racing roller rocker arms at all.


Last edited by Paul Kane on January 4th 2014, 11:29 pm; edited 1 time in total
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Re: Lucky catch

Post  Lem Evans on January 4th 2014, 1:35 pm

That broken gold comp rocker was/is a Scorpion sourced rocker. Seems that series rocker didn't stay in the catalog very long.  Laughing 
 
Myself and others have put lots of laps on the FRPP blue Crane rockers with the same TFS head/spring package [250# seat - 800# open]that David Cole shows in his picture w/o any breakage.

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Re: Lucky catch

Post  David Cole on January 4th 2014, 4:01 pm

Paul Kane wrote: Frankly, I don't think they should be allowed to be advertised/sold as racing roller rocker arms at all.

Exactly. They claimed these rockers as being good for .950 lift and 950 lbs spring pressure. Not by a longshot. They are still advertised on Scorpions page with these specs. To Comp's credit, they did honor their lifetime warranty (the reason I bought them). The replaced the broken one within a week no questions asked. I'm betting they ran into this issue more than once and that's why they are no longer listed by Comp.
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Re: Lucky catch

Post  Larry T on January 4th 2014, 9:57 pm

For what its worth im glad this post came up about the rockers thank you rick.

the stainless steel or chromoly steel rockers is what I am going to use.i think I am in the similar spring and cam package as david over .800 lift with a 1.73 rocker.i am sure the steel rockers have less deflect than the aluminum rockers that's what makes them better in my mind.

yes the Magnum1830-16 Ulta Pro XD rocker is on my radar but im not sure if my springs are over 1.550 dia.i will have to check that,thx
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Re: Lucky catch

Post  kim on January 4th 2014, 10:56 pm



I run these in 1.8 ratio

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Re: Lucky catch

Post  bbf-falcon on January 4th 2014, 11:45 pm

No one STILL has convinced me in this thread that MY rocker or David Coles rocker broke because it was what your saying is a middle of the road rocker. I will agree that the stainless deal would seem to be a stronger body design,but Davids deal COULD have been a weak or fatiqed chunk of aluminum and even a piece of stainless could do the same thing. I showed my rocker pic to a expert in the field of manufacturing and he told me it was his guess that when they pressed the needle bearing housing in my rocker at the factory,that they could have cracked the needle housing . And like the Crower/Comp or any other piece that is mass produced ,it won't be caught until it fails. SO,imo your "so called" high end rockers are just as apt to fail as the the lower priced ones. What about the "high end " shaft rocker deals that we have seen over the last few months such as George Keowns or Dan Hobbs .

Does anyone know who's valve components that Roush/Yates use?

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Re: Lucky catch

Post  Lem Evans on January 5th 2014, 12:09 am

'yes the Magnum1830-16 Ulta Pro XD rocker is on my radar but im not sure if my springs are over 1.550 dia.i will have to check that,thx"

1.640" dia. spring is not an issue.

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Re: Lucky catch

Post  whatbumper on January 5th 2014, 12:27 am

bbf-falcon wrote:
Does anyone know who's valve components that Roush/Yates use?  

Jesel J2k

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Re: Lucky catch

Post  Lem Evans on January 5th 2014, 12:55 am

Dave Cole's rocker failed because it was not suitable per the application....it was not the only report I've had of the comp ultra gold rocker breaking in that application.

"Does anyone know who's valve components that Roush/Yates use?"

Stuff that you or I could not call up and buy from a vendor.

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Re: Lucky catch

Post  DanH on January 5th 2014, 2:11 am

JR/R cup stuff today, most wouldn't want to deal with it. Plus NASCAR engines don't see the lift and spring pressure of the drag engines

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Re: Lucky catch

Post  c.evans on January 5th 2014, 2:40 am

whatbumper wrote:
bbf-falcon wrote:
Does anyone know who's valve components that Roush/Yates use?  

Jesel J2k
 
Lawes Mayfield has about eight complete Roush/Yates engines here in his shop now.  These engines do NOT use Jesel J2K stuff. Their rockers are steel rockers and are made in house. They are of the Mohawk design, and they have no adjuster in the body, just a hardened cup. The valve adjustment is done by either of three ways. 1. Lash caps that vary in thickness by .001". 2. Paper thin shims under the rocker stands. 3. Adjustable pushrods with .002" shims between the pushrod and it's pressed in tip.
 
As was mentioned previously, they don't run near the valve spring pressure in those small block NASCAR engines, that we run in big block drag race engines.
 
Getting back to Rick's bad bearing.  Often times even USA made rocker arms use bearings that are made overseas.  That doesn't mean they are necessarily a bad thing.  What I have learned on these caged needle bearings is that the wall thickness of the cage is different on the two sides of the bearings.  The side of the bearing that is the thickest and strongest is the side with the lettering and numbers on it.  That is the side you are supposed to press on. The other side is thinner and should not be pressed on.
  
In the photos that David Cole posted, it seems to me that the crack formed from the stress risers that were induced into the alum. rocker body when the steel cup with serations was pressed in.

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Re: Lucky catch

Post  bbf-falcon on January 5th 2014, 6:20 am

Charlie is correct. Roush/Yates purchases their material from a highend shop that manufactures the parts to RYR specs and they keep documentation on the steel that is used for that part. Then they have inhouse inspectors that sonic check and mag each part before it is assembled. The manufacture for most of these parts is one of my best friends and has ask me to please not mention his name or shops name. Charlie and Lem also know who it is also. Here is a message that he sent me about this thread.

[color=#ff3333]Rick IMO there is no way to be 100% sure that a problem before assy can be found unless they take the precautions we do and RYR does before the parts are put in the rockers.

I make components for roughly 15,000 rockers per year. I have had I failure and it is still yet to be determined what was the cause. Now imagine how many parts Crane and all the others make. There is no way they are going to pay someone to sit and do 100% inspection on those parts. We as racers couldn't afford it.
I really feel deep down that they know there is going to be some failure in the field and that's why they give a free replacement, Cheaper to give a free rocker than 100% inspection.

I imagine when they machine all these parts they have gaging and inspectors and Heat treat certs but unless you have 100% inspection as Nascar does there will be problems.

Just don't mention my name with that RYR stuff.

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Re: Lucky catch

Post  whatbumper on January 5th 2014, 1:04 pm

Sorry, the used stuff we bought from them off a cup motor had those rockers so I assumed they ran them.


We run T&D stuff with spring pressures you would spit coke out of your nose if I said and don't have issues. That's with some crazy offsets too.


On our old setup we ran the stainless crowder arms with zero failure.

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Re: Lucky catch

Post  Paul Kane on January 5th 2014, 1:37 pm

It is my understanding that the Winston Cup guys have been making their own rocker arms for themselves as far back as the 1990's, first starting with purchasing other brands (such as Jesel rockers) and modifiying the rocker arms after receiving them, then pulling the entire rocker arm manufacturing process in-house for their specific engine program. No-one should be surprised that the upper-end parts makers record and maintain source material heat lots and certifications...not doing so would be downright stupid business practice. Over in this camp we've been making rocker arms in both aluminum and chromoly for years, even making rocker arms for one of the biggest names in the valve train industry, and some of which that must withstand Top Fuel spring pressures and still not break.  But so what? Not a shred of this portion of the discussion--Top Fuel, high rpm roundy-round, top shelf rockers or whatever--applies to the original topic of this thread.


bbf-falcon wrote:No one STILL has convinced me in this thread that MY rocker or David Coles rocker broke because it was what your saying is a middle of the road rocker....Davids deal COULD have been a weak or fatiqed chunk of aluminum and even a piece of stainless could do the same thing. I showed my rocker pic to a expert in the field of manufacturing and he told me it was his guess that when they pressed the needle bearing housing in my rocker at the factory,that they could have cracked the needle housing . And like the Crower/Comp or any other piece that is mass produced ,it won't be caught until it fails. SO,imo your "so called" high end rockers are just as apt to fail as the the lower priced ones. What about the "high end " shaft rocker deals that we have seen over the last few months such as George Keowns or Dan Hobbs .

I, for one, didn't realize anyone was supposed to convince you of anything--this is a "Lucky Catch" thread that seems to have been posted as little more than a show-and-tell dealio. And the subsequent discussion about the failure that comes from the intial posting is typical.

That said, your Crane rocker arm was exonerated way back on Page 1, not that you implied back then that you were soliciting for answers. And contrary to your presumptions about the example of the broken rocker arm that Mr. David Cole posted, in fact it is not uncommon to see that rocker arm fail as such when used in the big spring appilcation as was his. We've observed rocker arms from that manufacturer failing numerous times, both breaking at the back end as pictured in this thread or splitting at the bottom of the body below the trunnion (between 5 o'clock and 7 o'clock). Just the fact that they often (ie, more than any other brand of which I am aware when put under the same circumstances) fail like that should spell out that this is not a fluke nor isolated situation due to a "chance" stress riser.  And while I'm not under any obligation to anybody to reveal the primary reason for their weakness, I will go so far as to say that if one studies the manufacturer's webpages long enough the answer should slap them in the face as it is the one, single detail that seems to be intentionally omitted from that overly compensating, shiny website of theirs.  And when you call and ask them about that missing detail, they first try to mislead you and when you ask for specifics boy do they get tight-lipped awfully fast. But hey, if their rocker arm completely destroys your entire engine they owe you nothing but a replacement rocker arm. As far as I'm concerned, that's what their "lifetime warranty" is really all about.

Lastly, properly set up and installed high-end rocker arms are not as likely to fail as low-grade rockers or even mid-grade rockers, and for the very reasons that you noted about quality control in your post above.  Also, at the time of this writing offshore (mainland china) bearings of all types are indeed causing all kinds of problems in the automotive industry and even elsewhere. Within the automotive industry, they are causing horrid problems in rocker arms, and in automotive wheel bearings for example.  Overall the American bearings are still superior, yet of course there are mass production oversights such as seems to be in your crane rocker arm. That's does not make the American bearings junk and yes it is an occassional consequence in mass production manufacturing that can occur in any end product in which they are installed.
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Re: Lucky catch

Post  466cj on January 5th 2014, 4:10 pm

That Comp Cams Arc Ultra gold rocker arm referenced on page 2:

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=19045-16&Category_Code=

If you look at the bottom of the page they state not for use over 700 lbs. valve open pressure.

Comp Cams is ISO 9001:2008 Certified so they do have a recognized quality system for design and manufacture.

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Re: Lucky catch

Post  Paul Kane on January 5th 2014, 5:34 pm

466cj wrote: That Comp Cams Arc Ultra gold rocker arm referenced on page 2:

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=19045-16&Category_Code=

If you look at the bottom of the page they state not for use over 700 lbs. valve open pressure.
This is a very interesting obeservation that you made, that the seller of the gold rocker is recommending a maximum open spring pressure that is 250 pounds less than what the private labeling, source supplier recommends on their own rocker arms. One has to wonder why that is...could it be that the gold rockers were failing so often that the seller wanted to discourage warranty returns due to higher open pressures? Could the lower rating be due to the slight difference in general shape from the supplier's rocker arm? Only the seller can given us the answer...

466cj wrote:Comp Cams is ISO 9001:2008 Certified so they do have a recognized quality system for design and manufacture.  
I am a course completed, exam passing, real-world experienced, Certified ISO 9000/2008 Auditor. And in the world of engineered products that are supposed to be suitable for the application in which a component is to be used, ISO means basically nothing.  ISO 9000 series certification means only that there are quality management programs in place geared towards continuous improvement of the manufacturing process, not necessarily the engineering process. It means extensive record keeping throughout production and if problems arise, they are investigated, documented, recorded, corrected, and forever traceable (say what you're going to do, do what you say, and write it all down).  Unfortunately, ISO Certification does not automatically garantee in any way the the end product is a "good" one unto itself. It is more-so for process improvement and end-result consistency.
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Re: Lucky catch

Post  466cj on January 6th 2014, 2:27 am

Paul Kane wrote:
466cj wrote: That Comp Cams Arc Ultra gold rocker arm referenced on page 2:

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=19045-16&Category_Code=

If you look at the bottom of the page they state not for use over 700 lbs. valve open pressure.
This is a very interesting obeservation that you made, that the seller of the gold rocker is recommending a maximum open spring pressure that is 250 pounds less than what the private labeling, source supplier recommends on their own rocker arms. One has to wonder why that is...could it be that the gold rockers were failing so often that the seller wanted to discourage warranty returns due to higher open pressures? Could the lower rating be due to the slight difference in general shape from the supplier's rocker arm? Only the seller can given us the answer...
The seller (Comp Cams) in this case is the one who is responsible for the product. Whether they manufacture it in house, or have it made by someone else it still is to their spec and their part. You can have two parts that look the same and NOT be the same. The fact is Comp Cams is the manufacturer as far as ISO is concerned, that is how it works and you know that.

Fact that they state for use up to 700 lbs valve spring force means just that. You are correct in that you know nothing of the reason why. I'll say is commendable that Comp Cams gives a warranty on their products and not just says too bad, that is racing like so many others do.


Paul Kane wrote:
466cj wrote:Comp Cams is ISO 9001:2008 Certified so they do have a recognized quality system for design and manufacture.  
I am a course completed, exam passing, real-world experienced, Certified ISO 9000/2008 Auditor. And in the world of engineered products that are supposed to be suitable for the application in which a component is to be used, ISO means basically nothing.  ISO 9000 series certification means only that there are quality management programs in place geared towards continuous improvement of the manufacturing process, not necessarily the engineering process. It means extensive record keeping throughout production and if problems arise, they are investigated, documented, recorded, corrected, and forever traceable (say what you're going to do, do what you say, and write it all down).  Unfortunately, ISO Certification does not automatically garantee in any way the the end product is a "good" one unto itself. It is more-so for process improvement and end-result consistency.

Very impressive Paul. Just so you know I spent a lot of years in medical devices before I got out. I grew up in medical electronics which included design and manufacture. Being we made medical devices I am very aware of ISO, FDA QSR's, and a good number of other things. I am well aware of what it takes to have a successful manufacturing business.

later I worked for a subsidiary of a at that time $120M year medical device manufacture that sold globally. My last title was "Quality Manager". Among my responsibilities included both regulatory compliance and submissions for both FDA and Health Canada. I routinely dealt with product issues and had to interface with engineers, product managers, upper management, and customers. Just so you know where I am coming from since you took the time to share your credentials. BTW I've dealt with my share of auditors, and been in that roll too... I don't like auditors just for the record  Smile Suspect 

Now then... a product only has to meet the expectations of its design (and any regulatory requirement if there is one) and if the design is sub par that is ok as long as it is manufactured according to spec., and sold according to spec., but ISO also is to have systems in place to detect failures, complaints, and trends; all of which is to be feed back to management to review and take appropriate actions.

When a company is certified there is an outside body who certifies then. They will be audited every so often and if the complaint file, trends, and failures are not being addressed it will be noted and questioned. If the manufacturer wants to ignore this at some point the certifying body will drop that company. Comp Cams is certified and that tells me something about them. [/quote]

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Re: Lucky catch

Post  supervel45 on January 6th 2014, 7:14 am

Very good info from Paul and 466, and everone else.                                                                          My question is what kinds of certification is used by NASA on space shuttle parts, and nuclear power plant eguipment?                                                                                                                                 We all remember two space shuttles crashing , and Three Mile Island. I get that the ISO9000 is a higher certification than ISO, but human error does figure in to all of them, as well as acts of God, and how much higher does the inspection certifications go from these, and the others mentioned?                                     The in house Roush/Nascar is probabaly miles ahead of the off the shelve rockers, but at what cost, are you willing to pay, if you could even get it. Someone mentioned zero failure on a certain rocker arm. That means it has not failed yet in their sample of use with said rocker, not that it will not fail, as all parts fail evenventially under use, and some even not under use, from age deteriation.                                        The China problem, and the not wanting to point fingers at a certain brand (not that anyone did that,nessisarly) and dance around a specific problem, or design defect, so as not to offend a supplier (possiably?), also makes me wonder even more about the state of the industry, and where it's headed?                                                                                                                   This issue, reared it's ugly head in the crankshaft thread, somewhat, also. If I was  going to run 750lbs or more spring pressure and a mechanical roller cam on a high dollar engine, I would be willing to spend quite a bit of money on higher end rockers(and they would not be aluminum, personally, not that aluminum RR's, won't work)  roller lifters, valves, and retainers,ect. than I would on an engine running 3-400lb spring pressure. Great thread this turned out to be and alot of good info, Thanks.

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ISO 9000 certification

Post  68galaxie on January 6th 2014, 1:18 pm

ISO 9000 and other "quality" certifications do not mean a product that is manufactured is "high quality" as we normally define high quality.
ISO certifications are a manufacturing and inspection protocol that the manufacturer develops and follows.
ISO certifications only ensure that a product is made/inspected in a repeatable way that the manufacturer has said they would do.

This does not mean the product is "high Quality" as we would define it. One could make an inferior product in a very repeatable way and
it could certainly be by an ISO9000 certified manufacturing company.
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Re: Lucky catch

Post  Paul Kane on January 6th 2014, 1:34 pm

466cj wrote: ...BTW I've dealt with my share of auditors, and been in that roll too... I don't like auditors just for the record  Smile Suspect
   Heh, I've been on both ends (as the auditor and as being audited) so I get the joke. Smile

466cj wrote:...but ISO also is to have systems in place to detect failures, complaints, and trends; all of which is to be feed back to management to review and take appropriate actions...and if the complaint file, trends, and failures are not being addressed it will be noted and questioned. Comp Cams is certified and that tells me something about them.
Acknowledged and duly noted that engineering is within ISO 9000:2008, however I say "not necessarily the engineering process" because this can be easily dodged and certainly so in this particular situation. In this particular case, of all the parts that CompCams sells--springs, retainers, locks, rocker arms, camshafts of all types, etc--they manufacture almost none of it. Making engineering changes is far more involved and they can turn to other ways to solve issues, such as simply lowering the maximum spring rate.....hey, we might have just hit on something: CompCams is in the valve train business, and if they are getting a lot of these rocker arms failing in the field and being returned their customer techs are probably wise enough to ask very specific valve train questions such as the end user's max spring rate, end user's peak rpm, etc. And maybe, just maybe, based on all of the end user's valve train data being gathered their ISO-documented fix was to lower the maximum spring rate on their outsourced rocker arm.  That would be a cheaper "fix" and is a perfectly legitimate way to address the problem under ISO standards.  I have no idea whether or not CompCams ever offered this rocker arm with the manufacturer's (higher) recommended spring rating, but if they did and then lowered it under these circumstances it would certainly be in their records. Smile

On the other hand, the parent company manufactures the rocker arms (among other stuff). All the countless end user's of their rocker arms do not call them for spring recommendations for a certain cam profile, or call to ask if a stud girdle is necessary, etc, as the end user's of CompCamps products much more likely would (ie, not anywhere near the same number of Q&A tech handling over all kinds of valve train matters as CompCams).  So, when the manufacturer's rocker arm breaks and is returned, more often the manufacturer probably sends them a replacement no questions asked. <---- And here-in lies the loophole for engineering and ISO. "We cannot determine why that rocker arm failed--the end user might have exceeded the maximum spring rate, and on this one the combusted cylinder pressures might have been greater than the maximum spring rating (holding the exhaust valve closed), and on this one the geometry might not have been optimized and the loads on the rocker were in excess of what is normal, and on this one the valve hung up/got stuck and that's not the fault of the rocker arm." To some extent it's the manufacturer that sets a lot of the rules for itself, and an auditor would have to be a racing engine expert to see through such claims and impose some kind of further investigation. BTW, the parent manufacturer states that they became ISO certed only in 2012 so they've had plenty of breathing room for the many years that they've been in business, and may still be able to state that they don't have enough data from the field.
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Re: Lucky catch

Post  Paul Kane on January 6th 2014, 1:43 pm

Paul Kane wrote:... in fact it is not uncommon to see that rocker arm fail as such when used in the big spring appilcation as was his. We've observed rocker arms from that manufacturer failing numerous times, both breaking at the back end as pictured in this thread or splitting at the bottom of the body below the trunnion (between 5 o'clock and 7 o'clock)...









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Re: Lucky catch

Post  supervel45 on January 12th 2014, 3:19 am

kim wrote:

I run these in 1.8 ratio
Paul do you have any pic's of a similar body failure of a SS or cromemoly rocker, or have you not had or seen one yet, like on the aluminum body RR pic's you posted?

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Re: Lucky catch

Post  Paul Kane on January 12th 2014, 12:37 pm

supervel45 wrote:Paul do you have any pic's of a similar body failure of a SS or chromoly rocker, or have you not had or seen one yet, like on the aluminum body RR pic's you posted?
I'd think you could ask anyone if they've seen a failed steel rocker...I haven't but anything is possible, especially when set up incorrectly.

If you asked me specifically because of the images of broken rockers that I posted, then I hope I've been clear that I am not bashing aluminum rocker arms in general. In fact I mentioned earlier in this thread that I believe well designed aluminum rocker arms are up to the tasks in most builds. The pics that I posted focus around a very specific product/manufacturer only, not all of them in general.  Most aluminum rocker arms in general are plenty strong for the intended applications.
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