l2r99gst

iTrader: (2)

denver,

I think Greg is just suggesting that if the cam was sound, normal operation wouldn't cause this type of damage. The only way Greg was able to replicate a similiar failure was by first overtorquing the cam with an impact gun and then breaking it with a sledge hammer.

So, I think Greg's point was that a cam can break like this under certain circumstances, most likely not from proper operation of the cam, maybe suggesting improper installation, etc.

I don't think we should take sides with either party here...all I suggested is that the cam be tested by a failure analysis/metallurgy lab to see the real cause of failure. If installation/improper use and handling caused it, then it's the client's fault. If it truly is a cam defect or microstructural defect, then the manufacturer should cover the costs.

EVOIXMR8916

iTrader: (8)

i have some followers/rollers for sale that only have 6k on them if u need any!!! pm me can ship out sameday if payment is before 10:30pm CST!!!

Thanks,
-Dan

denver

iTrader: (9)

I completely agree with you, a cam machined and treated properly will not fail under normal or extreme operation.

I 100% agree with your last statement, but have not seen GSC (Greg) even acknowledge that his product (this set of cams) could have a problem. I am with you, I want to know the cause, and depending on the results the customer, or the manufacture make things right.

Manufacture - take ownership and replace the damage part and the damage caused by the part
The Customer - express to the evo community the product was correct, and the failure was a result on abuse etc...

tnt1106

Guys,

There are no "sides" in this discussion. There is only what really caused this camshaft to fail. That is why I am not posting conjecture, only the factual information. That is also why I had the motor carefully disassembled and inspected as to ANY possible cause of failure on the camshaft.
I would not post assuming it was a defect in the camshaft with out first eliminating all other possibilities.

I am certain however that I did not send my cam shaft to Comp Cams, so I would really appreciate if anyone posting in this thread please be sure of their facts before claiming to know what I have and have not done thus far.

GregGSC

iTrader: (44)

ACTUALLY the old Evo 8 Simi finished cam that KTK had an issue with is made by a different Manufacture on a different side of the world. The same manufacture in Taiwan that makes the simi finished core that KTK had this issue with is the same manufacture that Comp Cams uses for FP's Evo 9 Cams.. We stopped using those cores in 2006 when our rejection rate grew to over 50%. The newer cores are manufactured in Europe, half way around the world. This would include your Evo 9 Cams. So long story short is it is virtually impossible for the issue to be linked. IE different design, different metal, different manufacture, different country. Also the first batch of cams we ever ground up for the evo was a ductile induction hardened core, and our new cam is a chilled billet.

Here are a couple of other facts for you.

The same exact cam core you have is used by Cosworth, Brian Crower, Kelford, and GSC.

GSC alone has sold 497 of these S2 cams since 2006, which does not include the S1 grind which is also ground on the same simi.

After checking with other manufactures it seams there are only 5 known failures such as this. Roughly 2k plus Evo 9 cams that use the same billet are running in cars with well over 8k miles on them… with only 5 known failures that is less than a 0.25% failure rate.

2 of the other cam failures were located on the other oil grove or the back grove; one was located behind both of the oiling groves. Ie it is not isolated to the spot for which you believe is a problem.

Your cams have been in use for 8k miles.

Destructive testing only yielded a similar break after over-torqueing a cam bolt and hitting it the gear with a sledge hammer… trust me your engine should never put this much abuse on a gear or cam… ever.

Now you have sent these cams and gotten feed back from competitor camshaft companies before you even bothered to contact GSC about our own product.

tnt1106

[QUOTE=GregGSC;6718933Now you have sent these cams and gotten feed back from competitor camshaft companies before you even bothered to contact GSC about our own product.[/QUOTE]


Greg,

This shows how much you just assume or are misinformed. I will restate what I said above.




I DID NOT SEND MY CAMS TO ANY COMPANY THAT MANUFATURES CAMSHAFTS TO BE TESTED AS TO REASON OF FAILURE.


I am not looking to "blame" this failure, only show all my fellow Evo owners that spend their hard earned dollar as to why this failed and hopefully help them avoid my mistake.

In fact, I have never contacted Comp Cams, Kelford, HKS, nor any other camshaft manufacturor at all.


Ok. Now that that is out of the way. The very first thing I did after having the motor disassembled was to contact you. In point asking how you wanted to proceed. Rather than asking me to send you my camshaft to determine what happened all you have done is feed reasons and excuses as to why it is not possible for your cam to have failed.

Once the results return from the lab (awaiting eletron microscope scan) as I stated I will post them. I have no problem in showing if / how I fractured this camshaft. If it turns out that I caused this failure you will get my full suport of your product.

8 thousand miles is a long time to run any camshaft that is improperly installed. It is also a very short time to experience a timing belt, tensioner, or pulley failure. Again which would show a different pattern of fracture not the one in above pictures that were sent to you only days after the failure.

GregGSC

iTrader: (44)

how did i get an email on January 22nd from a competitor of your pictures when you didnt send them to me till the 23rd?

Cirrusly Evolvd

iTrader: (44)

I'm wondering why he's still holding GSC responsible for this when Greg has pretty much stated that multiple branded cams are made by the same company? Are you gonna fight as hard to warn everyone about those cams as well?

C6C6CH3vo

iTrader: (9)

Question (regarding KTK's case with the non-S type: The lobe recieves a good part of lube from the roller assy which is supplied by top of lash adjuster. The damaged area in KTK's case is where the roller achieves peak acceleration (valve close) and is where heat is most likely.

What are the chances chronic heat can play a role from lack of lube such as the case of a ticking lifter?

Julian

WE had a similar issue with a set of cams from GTM Motorsports in Cali, for a 350Z.The tops of the lobes broke off like that, most likely from a casting defect or impurity. The manufacturer would not warranty them and told us that we used to low of a Zinc content oil and the cams did not properly hardenI kid you not...I knew it was BS and for the record we were running Rotella for break in, and it has one of the highest Zinc contents available...lulz..

Your cams look like a casting defect, if they are from 2005, Im guessing your not covered. However you better check your bottom end bearings, cause all that metal had to go somewhere in the oil...

I would have a hard time believing that valve float cause that, and that the valve is still in the engine, and functioning...

tnt1106

If you received pictures from another source other than myself I have no knowledge of who sent those to you. I do know that the cams came out of the car, photographed, and were then returned to my possesion. At that point the cams were handed off (by me perosnally) to the lab (which is local). It's really moot point trying to discuss any of this further until I have the results in my hands. I will post a new thread with results as I mentioned earlier. Also would you forward me the email from your competitor if it is not priveledged information? I would like to see it. Thank you.


Ktk,

I am very glad you are being treated properly thus far and wish you the best of luck with your car in the future.

ktk

iTrader: (9)

OK so I finally got around to doing a decent inspection and search for collateral damage on my motor.

Started by taking off one of the cam bridges just to see if there was any visual indication of scoring due to metal fragments in the oil. Nothing, the surface of the cam and the bride both looked fine. good so far. Next was to drop the oil and filter. Upon doing so I found a few tiny flecks of metal in there which scared me so I collected a sample of oil and am having it analyzed at an oil lab as we speak.

Then I decided to drop the oil pan. My frekin god that thing was a pain. The RTV on there was like JB weld or something. Even after pulling all the bolts out and whaling on that thing for 30 mins with deadblow hammers it wasn't trying to budge. I remember thinking we could've just ditched all those bolts for weight savings, the gasket held it more than tight enough lol. Anyways we managed pry it off finally and dropped that dude. First thing i noticed when was looking in the pan was that one of my piston cooling oil squirter nozzles was chillin in the bottom of the pan.

I have no idea how that thing ended up in the pan. It can't be related to the cam issue. My only guess is, it must've been slightly off position during the original build and been bonked off the first time the engine was fired up and landed in the pan???

Anyways, then i got under again and found that piston 3 was missing its oil squirter nozzle. So i decided to pull the end of the 3rd rod off to see if the rod bearing was ok. I pulled the rod cap off and it looked fine. No signs of anything unusual or grinding by metal in the oil. The crank looked even better. Not a single sign of any damage at all, it looked perfect, brand new.

Then we were cleaning up and I noticed that the oil sump had a little course mesh filter in it as a safety to prevent anything big form being sucked into the engine. Well THANK GOD for that course filter it saved my engine. There were lots of little sharp fragments of what looked to be BROKEN CAM in the filter. We busted out the magnet and got as much as we could out of there. Check the pictures to see what we got out.

So all in all a productive day. Preliminary inspection seems to show that there is no major bearing damage. I found some of the missing metal in the sump filter. I am having an oil sample analyzed at the oil lab and I am going to get one of my technician buddies to cut open the oil filter at work tomorrow so I can see whats up in there. Maybe the rest of the metal will be in there hopefully!


So next step will be to start ordering parts. I think I will take up Greg@GSC on his offer to replace my defective cam with a new GSC S2. I will have to replace that broker oil squirter but I think I can access it pretty easily so hopefully that is not a big issue, I'll talk to my engine builder about it.

Now here is the question for you guys: I'm thinking it would be wise to replace the roller followers as they were in direct contact with the damaged cam and at least one of them has taken a beating at that damaged lobe. Visually they look fine but what do you guys suggest? And what about lifters?

I'm also thinking of doing timing belt (and balancer belt, yes i have a shaved balancer shaft in my stroker evo) at the same time. Any recommendations for timing belt brand/deals?

Summary:

1) Should I replace roller followers and/or lifters?
2) I want to do timing belt & balancer belt now that the car is opened up anyways. Recommendations of belts/deals and any tips on how to best go about replacing the belt (it looks to be a pretty tricky piece of work from what i can see)

ktk

iTrader: (9)

Any of you guys who have experience with combined cam swap with timing belt replacement please chime in with any tips.

1) what all is usually replaced as part of the timing belt service?
2) should i get the "timing belt tool"
http://www.lancershop.com/customer/p...?productid=675


thanx!

Cirrusly Evolvd

iTrader: (44)

Change your tensioner, balance shaft belt and accessory belt as well...might as well since it's such a PITA. And your shop should have the timing belt tool...the lancershop one is cheap and flimsy...better off threading your own out of steel rod stock.

C6C6CH3vo

iTrader: (9)

Good to here your in the clear so far + a brand new set of S2's.

I would replace the lifters, roller arms, timing belts, water pump, alternator, assy belt, and perhaps idlers and tensioner (manditory) and whatever the new S2's require. I would also flush the entire sump/oil circulation system with something recomended (I don't know - kerosene?) and follow FSM for installing lifters and cams. Take your time to get it right.




As far as the other problem with the mivec cam, seems to be happening with other cams too:
https://www.evolutionm.net/forums/ev...m-snapped.html