[Z06] Another busted exhaust valve
06-24-2012, 03:50 AM
#41
My heads not in the sand. If you have looked at my other posts in threads of the same subject matter you would know that I totally agree that there is an issue. THIS PARTICULAR CASE is what I am referencing. My question is how many of the failed vehicles were bought of the showroom floor and how many were bought pre-owned? I have seen in many instances where an individual leases a car just to "have one" turn's it in with 2 or 3k miles on it after driving it like a mad man for 6 months. Dealership gets it, sells it as a certified pre-owned car and the new owner thinks he's getting a steal. few months to a year later the car is back in the shop getting a new motor or drivetrain. Not the new owners fault, he drove the car like a saint.
Another interesting thing here, is that if this had been say a grand sport, or other LS3 equipped Corvette, and this same thread had been placed in C6 General, along with the history, the outcome and what happened, the reaction would be completely different.
Many in such a thread, would be referring to the driver as a dunce, an idiot, and having gotten what he deserved. Some would even say that they didn't blame GM for not covering it
However in here, the thread in part because of it's alarmist, almost P.T. Barnum type showmanship title, becomes an indictment of GM, the LS7 as a whole, and it's valves.
This was a clear case of a car failing under abuse, and had it not been abused, it would still be running.
The guy was doing 1st and 2nd gear doughnuts and smoke shows before the engine finally crapped out.
Of course that tidbit will fall on deaf ears because it is not quite as sensationalistic as "Another Busted Exhaust Valve". But it is nonetheless, true.
A more appropriate, and accurate title for this thread would have been "Z06 Engine Fails After Clear Abuse, GM Denies Warranty".
But again, that's not going to stay at the top of the page for a week, like "Another Busted Exhaust Valve" will.
This instance of straight up abuse, just to see how far the car can take before it pops, is about to make one of us pull his heads and have the exhaust valves replaced.
Amazing.
Last edited by '06 Quicksilver Z06; 06-24-2012 at 03:57 AM.
06-24-2012, 06:36 AM
#42
Le Mans Master
And as far as the A/F ratio, the car would adjust itself.
06-24-2012, 06:40 AM
#43
Le Mans Master
You know as I look at this particular incident, I am not seeing it as an indictment of the LS7, but nonetheless it is an interesting thread in some of the reaction it has generated.
Another interesting thing here, is that if this had been say a grand sport, or other LS3 equipped Corvette, and this same thread had been placed in C6 General, along with the history, the outcome and what happened, the reaction would be completely different.
Many in such a thread, would be referring to the driver as a dunce, an idiot, and having gotten what he deserved. Some would even say that they didn't blame GM for not covering it
However in here, the thread in part because of it's alarmist, almost P.T. Barnum type showmanship title, becomes an indictment of GM, the LS7 as a whole, and it's valves.
This was a clear case of a car failing under abuse, and had it not been abused, it would still be running.
The guy was doing 1st and 2nd gear doughnuts and smoke shows before the engine finally crapped out.
Of course that tidbit will fall on deaf ears because it is not quite as sensationalistic as "Another Busted Exhaust Valve". But it is nonetheless, true.
A more appropriate, and accurate title for this thread would have been "Z06 Engine Fails After Clear Abuse, GM Denies Warranty".
But again, that's not going to stay at the top of the page for a week, like "Another Busted Exhaust Valve" will.
This instance of straight up abuse, just to see how far the car can take before it pops, is about to make one of us pull his heads and have the exhaust valves replaced.
Amazing.
Another interesting thing here, is that if this had been say a grand sport, or other LS3 equipped Corvette, and this same thread had been placed in C6 General, along with the history, the outcome and what happened, the reaction would be completely different.
Many in such a thread, would be referring to the driver as a dunce, an idiot, and having gotten what he deserved. Some would even say that they didn't blame GM for not covering it
However in here, the thread in part because of it's alarmist, almost P.T. Barnum type showmanship title, becomes an indictment of GM, the LS7 as a whole, and it's valves.
This was a clear case of a car failing under abuse, and had it not been abused, it would still be running.
The guy was doing 1st and 2nd gear doughnuts and smoke shows before the engine finally crapped out.
Of course that tidbit will fall on deaf ears because it is not quite as sensationalistic as "Another Busted Exhaust Valve". But it is nonetheless, true.
A more appropriate, and accurate title for this thread would have been "Z06 Engine Fails After Clear Abuse, GM Denies Warranty".
But again, that's not going to stay at the top of the page for a week, like "Another Busted Exhaust Valve" will.
This instance of straight up abuse, just to see how far the car can take before it pops, is about to make one of us pull his heads and have the exhaust valves replaced.
Amazing.
06-24-2012, 07:52 AM
#44
Le Mans Master
I'm staying stock.......and when I upgrade to the ZR1......I'm staying stock.
06-24-2012, 08:30 AM
#45
Pro
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St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10
Take your completely stock car to a safe place and do WOT 7K shifts in 3rd and 4th gear, then put on the brakes at 165 mph and explain to me why you need to modify the engine ??
The part I don't like about this is the "rubber in the wheel well" part. These cars are marketed as being ready for amateur-level, non-racing track events. Look at the 427 convertible commerical with Tommy Milner, look at the "just to be fair" commercial, etc. If you do any of that, there is going to be rubber in the wheel well. If I was denied on that basis on an otherwise completely stock car, I'de get a lawyer and fight until I won.
06-24-2012, 08:35 AM
#46
Drifting
Im so tired of hearing excuses that its not the exhaust valves fault... Its retarded... Our exhaust valves are totally JUNK and should be removed as soon as possible...
06-24-2012, 08:46 AM
#47
Team Owner
TJ...was the car tuned? I know we have been avoiding that question; however the engine was still modded but the tune really can be a defining factor especially if the owner was trying to get the most HP numbers out of the engine.
06-24-2012, 09:26 AM
#48
Team Owner
Doing a burn out isn't abuse IMO.
I can take my mustang out and do burn outs all day long without fear of stuff breaking, but if I do it in the z06 I have to worry about it coming apart and being "abused"? Give me a break.
"Take your completely stock car to a safe place and do WOT 7K shifts in 3rd and 4th gear, then put on the brakes at 165 mph and explain to me why you need to modify the engine ??"
Been there, done that. Boring. Needs about 2x the power.
I can take my mustang out and do burn outs all day long without fear of stuff breaking, but if I do it in the z06 I have to worry about it coming apart and being "abused"? Give me a break.
"Take your completely stock car to a safe place and do WOT 7K shifts in 3rd and 4th gear, then put on the brakes at 165 mph and explain to me why you need to modify the engine ??"
Been there, done that. Boring. Needs about 2x the power.
06-24-2012, 09:33 AM
#49
Melting Slicks
06-24-2012, 09:40 AM
#50
Safety Car
In my fairly extensive racing experience.... naturally aspirated pump gas under 7000 rpm motors with relatively fresh oil in them simply do not blow-up (very rare) Regardless of if it has headers or doing burn-outs and what have not. Gen 1 sbc's certainly do not blow-up at anywhere near this frequency that I have been reading about here.
Its my understanding our motors are hand built, that means the valve geometry is individually set-up by a fella and I know that our cylinder heads have a massive 2.20" intake valve, hence, no room for standard valve positions, thus both valves are offset, therefore requiring an offset rocker.... they are always tricky to set-up. In my opinion, this may not be so much about the exhaust valve as the guy who set it up. But, I don't know, just thinking out loud, I am new to the C6Z world..... so do not know much more than what I have read here in the last week or two, but in my opinion, definitely a problem with the valvetrain on our motors that GM should address.
Somebody (GM) needs to utilize spintron technology on these motors and reallly, really, reallly look at whats happening with the valvetrain in a test lab environment.
Anybody know if there is a definitive fix that we can do as preventitive maintenance ? Link ? Thanks....
Its my understanding our motors are hand built, that means the valve geometry is individually set-up by a fella and I know that our cylinder heads have a massive 2.20" intake valve, hence, no room for standard valve positions, thus both valves are offset, therefore requiring an offset rocker.... they are always tricky to set-up. In my opinion, this may not be so much about the exhaust valve as the guy who set it up. But, I don't know, just thinking out loud, I am new to the C6Z world..... so do not know much more than what I have read here in the last week or two, but in my opinion, definitely a problem with the valvetrain on our motors that GM should address.
Somebody (GM) needs to utilize spintron technology on these motors and reallly, really, reallly look at whats happening with the valvetrain in a test lab environment.
Anybody know if there is a definitive fix that we can do as preventitive maintenance ? Link ? Thanks....
06-24-2012, 09:48 AM
#51
Melting Slicks
The Z06 in its stock form beats 90% of the cars on the road. Modding is addicting and fun and chasing the numbers becomes an obsession. My advice is if you can afford to pay then mod away. Otherwise don't cry when the motor blows and you have been modding and abusing it.
Its obvious the owner was abusing the car. You think this was the first time he did this? Ever meet a girl in a club and she takes you outside for some fun and she says "Ive never done this before" Yeah... ok. Sure you haven't.
Bouncing off the rev limiter beating the **** out of the car many times I'm sure in a most likely TUNED, headered, CAI Z06 sounds like a recipe for disaster. Anyone who says GM should cover this is out of their mind.
What makes me sad is that that LS7 cant take the abuse. You have some engines that you can really just beat the **** out of and it just takes it and asks for more. The LS7 is not that engine, or at least the valve train isnt.
Lesson to everyone. If you are going to mod and abuse the hell out of your LS7. Upgrade the valve train. If you are going to mod and actually take care of your car you probably wont have an issue, but if the small percentage of failure bothers you or you are not in a financial position to deal with the repair then keep your warranty and enjoy the Z in its stock form. Do an axle back and a CAI. Put in a short shifter and stick to the cosmetics.
06-24-2012, 09:58 AM
#52
Team Owner
I wasn't saying GM should cover this, but it shouldn't fail in the first place. There is no reason doing a burn out or driving the car hard to cause failures like this.
06-24-2012, 10:00 AM
#53
Something that is designed as two piece is weaker than something that was originally built as one. Get rid of the two piece valves and replace them with the one piece stainless and all is good. Modded or not replace them and the valve dropping issue is out of the equation.
06-24-2012, 10:01 AM
#54
Safety Car
True, but TJ says himself that this car was stomped on pretty good.
It pretty much left GM an out.
Doing burnouts on the street, I'm thinking that most auto manufacturers out there are going to consider that "abuse".
If this was a "big burnout" as TJ describes above, then there would have been plenty of rubber in the fender wells, on the shocks, and elsewhere.
He made it easy for them to deny coverage on it.
Big burnouts on the street, CAI and headers, I'm not thinking that the stock tune is going to be in a car modded and used like that.
If they looked in the ECM and saw that it was tuned, then that was just the icing on the cake for them.
But from the description you're giving, this would fall under the category of what most manufacturers call "abuse", Wil Cooksey not withstanding, and this was probably not the first time the car had been subject to this sort of exhibition before it finally failed.
It pretty much left GM an out.
Doing burnouts on the street, I'm thinking that most auto manufacturers out there are going to consider that "abuse".
If this was a "big burnout" as TJ describes above, then there would have been plenty of rubber in the fender wells, on the shocks, and elsewhere.
He made it easy for them to deny coverage on it.
Big burnouts on the street, CAI and headers, I'm not thinking that the stock tune is going to be in a car modded and used like that.
If they looked in the ECM and saw that it was tuned, then that was just the icing on the cake for them.
But from the description you're giving, this would fall under the category of what most manufacturers call "abuse", Wil Cooksey not withstanding, and this was probably not the first time the car had been subject to this sort of exhibition before it finally failed.
Quick how long are you going to continue to make excuses for this undeniable issue? It's seems to me because you have done all of this research and stuck to your guns every step of the way that no matter how many times this happens your going to make up some kind of theory for why it happened and you don't blame GM. Give it up already, there is a problem.
It's funny with the rash of broken exhaust valves lately I dont see the usual suspects step in to defend this anymore. Go talk to Del West, Ferrea, and other valve manufactures and ask them about the sodium filled stems. Go on the Ferrari forums and ask them, this is not a new problem, they have been breaking for 20+ years. They are not designed for long term use, they are used in race engines that are torn down after X number of events. They are a cheap alternative to Ti and that's why race teams (and GM) have used them.
It's time to admit that GM, who I believe had good intentions by using the sodium filled stems, made a huge mistake and needs to stand behind there product. We spend $75,000 for these cars and to say we won't fix your car cause you did a burn out?
Have you seen the new ad for the 427 vert on GM's site? They talk about what it is capable of doing while the professional driver is racing it, I am sorry to use your terms "abusing it" around the race course. So GM tells us this is a race car and advertises it on a track, but if you take it there you void your warranty.... Give me a break.
There wrong, we are right, end of story!
06-24-2012, 10:08 AM
#55
Melting Slicks
I agree. I wish you could just beat it as much as you want and it would take it. Not the case though.
How often did the owner do this? No way it was just this once. Id love to see the service history. Id love to see how he treated it. Did he just start it up and hammer the throttle before it was warmed up and the oil was circulated? Anyone who abuses the car as much as it sounds most likely could care less about letting it warm up before hitting it. It wouldn't take much if the valve train was oil starved a few times to cause major heat problems and wear it down over a short period of time.
I can tell you this, I have owned many many cars and not once have I ever did what the owner did to any of them.
Last edited by propain; 06-24-2012 at 10:14 AM.
06-24-2012, 10:09 AM
#56
Melting Slicks
Something that is designed as two piece is weaker than something that was originally built as one. Get rid of the two piece valves and replace them with the one piece stainless and all is good. Modded or not replace them and the valve dropping issue is out of the equation.
I wonder if this would void your warranty though? Anyone know? Seems like it would. Kinda defeats the purpose if your staying stock. Just keep your warranty up and drive without worry is my opinion.
06-24-2012, 10:09 AM
#57
Racer
Quick how long are you going to continue to make excuses for this undeniable issue? It's seems to me because you have done all of this research and stuck to your guns every step of the way that no matter how many times this happens your going to make up some kind of theory for why it happened and you don't blame GM. Give it up already, there is a problem.
It's funny with the rash of broken exhaust valves lately I dont see the usual suspects step in to defend this anymore. Go talk to Del West, Ferrea, and other valve manufactures and ask them about the sodium filled stems. Go on the Ferrari forums and ask them, this is not a new problem, they have been breaking for 20+ years. They are not designed for long term use, they are used in race engines that are torn down after X number of events. They are a cheap alternative to Ti and that's why race teams (and GM) have used them.
It's time to admit that GM, who I believe had good intentions by using the sodium filled stems, made a huge mistake and needs to stand behind there product. We spend $75,000 for these cars and to say we won't fix your car cause you did a burn out?
Have you seen the new ad for the 427 vert on GM's site? They talk about what it is capable of doing while the professional driver is racing it, I am sorry to use your terms "abusing it" around the race course. So GM tells us this is a race car and advertises it on a track, but if you take it there you void your warranty.... Give me a break.
There wrong, we are right, end of story!
It's funny with the rash of broken exhaust valves lately I dont see the usual suspects step in to defend this anymore. Go talk to Del West, Ferrea, and other valve manufactures and ask them about the sodium filled stems. Go on the Ferrari forums and ask them, this is not a new problem, they have been breaking for 20+ years. They are not designed for long term use, they are used in race engines that are torn down after X number of events. They are a cheap alternative to Ti and that's why race teams (and GM) have used them.
It's time to admit that GM, who I believe had good intentions by using the sodium filled stems, made a huge mistake and needs to stand behind there product. We spend $75,000 for these cars and to say we won't fix your car cause you did a burn out?
Have you seen the new ad for the 427 vert on GM's site? They talk about what it is capable of doing while the professional driver is racing it, I am sorry to use your terms "abusing it" around the race course. So GM tells us this is a race car and advertises it on a track, but if you take it there you void your warranty.... Give me a break.
There wrong, we are right, end of story!
06-24-2012, 10:19 AM
#58
Racer
Something that is designed as two piece is weaker than something that was originally built as one. Get rid of the two piece valves and replace them with the one piece stainless and all is good. Modded or not replace them and the valve dropping issue is out of the equation.
06-24-2012, 10:47 AM
#59
I don't think quick has ever denied that there is an issue. As a matter of fact he advocates that there is an issue and has research to back this up. What people, including yourself, are overlooking is the fact that he is speaking in reference to THIS OCCURRENCE. Obviously the guy who owned the car has beat the ever-loving **** out of it, even the member who is tearing the car down admits to that. So in that instance this is a driver induced incident. Can I say that an error in the valvetrain further induced and even aided in the carnage? YES.
Yes, I am indeed speaking of this occurrence, and this one only.
If this had been on Youtube, and had been ANY LS3 Vette in the lineup, there would be a chorus of "idiot" from those who had views the video and commented in the thread.
But because it was a Z06/LS7, now the "boo birds" come out. But really what else do you expect from a title like that used in the thread?
This thread is nothing more than sensationalism and discusses a car which failed after, or more accurately during being abuse.
The thread title though, will catch more eyeballs than "GM Denies Warranty Due to Blatant Owner Abuse."
This one is "easy" for those at the ready to blame "design flaws", "weak two piece valves" and other such, for this "failure".
Some are even trying to deny that it was abuse.
The owner of this car was abusing it, and had probably been abusing it prior to this incident, ..........and it finally broke out from underneath him during his "exhibition".
Same thing has happened to other makes and models for years.
However many of us, consciously or unconsciously, see it as a chance to harp on the "valve issue".
This was a car that broke because of:
.....
DH, guess that is a good question, or is it, which came first the chicken or the egg?? Its pretty tough to tell, there is so much damage. However I usually don't see a piston breaking unless something hits it or falls into the cylinder or its a hydraulic issue. Which in this case that isn't it. The customer told me he was doing some mean burn outs while showing off in first and second gears and doing donuts and such. That is when it blew up, he said it just quit running and he saw lots of white smoke and hear lots of clattering noise.
.....
DH, guess that is a good question, or is it, which came first the chicken or the egg?? Its pretty tough to tell, there is so much damage. However I usually don't see a piston breaking unless something hits it or falls into the cylinder or its a hydraulic issue. Which in this case that isn't it. The customer told me he was doing some mean burn outs while showing off in first and second gears and doing donuts and such. That is when it blew up, he said it just quit running and he saw lots of white smoke and hear lots of clattering noise.
.....
There is no denying that this car failed after being abused. This was certainly not "normal driving" for a "track" of any sort, unless you just won a NASCAR race, and certainly not normal for any streets that I can think of either.
If GM is denying this one on the basis of abuse, then I'd agree that it was.
Last edited by '06 Quicksilver Z06; 06-24-2012 at 10:52 AM.
06-24-2012, 10:47 AM
#60
Burning Brakes
I wouldn't be so quick to say that, there have been many failures with SS valves replacing the stockers....it's all about the setup. You can't just throw in a valvetrain and call it good. They only way to do that on a stock ls7 is to find a stronger exhaust valve that is very, very close in weight if not equal to the stock valve. In this scenario you have to look at the big picture. Staying high in the RPMs for extended periods of time while beating the rev limiter generates a lot of heat in not only the cylinders but in the heads as well. I'm sure everyone here has had at least a basic lesson in thermodynamics and transfer of heat/energy. Things get super hot and expand at different rates, weakening certain metals to the point of destruction (2 piece valve) and boom. No more engine. I would have like to seen what his engine/oil temps were at the point of failure.