[Z06] LS7 Engine Failures On CF....The Breakdown
07-30-2009, 11:56 AM
#81
Team Owner
Thread Starter
thank you so much
QS:
Thanks for taking the time to do this analysis. You've done the best analysis you could given the nature of the data. A few facts/points are in order for the people who seem to want to argue about this:
1. QS cannot possibly survey all 25K Z06 owners. He is limited to those who post here. Thus he is using a subset of owners to draw his conclusions. Generalizing this to the entire population of cars/owners is not perfect but is the best data that we have. GM is the only one who knows the true failure rate - ask them at the next BG event.
2. I'll stipulate that the CF user group represents a more aggressive group of drivers vs. those that do not post. Not bad drivers, just more likely to test the safety factor of the engine.
If this is true, then there is no doubt some sampling error in that we may be overestimating the true failure rate.
3. At this point, we'll have to make an educated guess with respect to the true failure rate. Since people are more likely to post when problems arise, let's assume that they wil post it here if they aware of this site or are a member. Let's assume that, conservatively, 10% of the Z06 community posts or is capable of posting here. Then we have ~8 failures out of 2500 or so cars let's round to 10/2500 for simplicity. Now we have a failure rate of 0.4%. This probably over-represents the true failure rate but is the best we can do....
4. Others have posted that there is a problem with this engine that is being ignored. Yes and no. QS's methods (to reject those cars with modified tires or suspension) in one sense ingore the oiling issue as they would tend to mask this problem. However, since GM did not design the car to operate with coilovers or tires meant to add grip on the track, he is just simplifying the analysis as he wants to know how likely a stock car is to fail. This does not imply or prove there is not a "problem" with the LS7 - clearly it has some weaknesses such as the oiling system and, in an isolated group of units, bad rocker arms... However, people get really caught up in the N=1 problem - they read a few cases online and assume that every LS7 is failing or has some fundamental design flaw that will lead to a majority of LS7's failing under normal operation- this is not true.
Thanks for taking the time to do this analysis. You've done the best analysis you could given the nature of the data. A few facts/points are in order for the people who seem to want to argue about this:
1. QS cannot possibly survey all 25K Z06 owners. He is limited to those who post here. Thus he is using a subset of owners to draw his conclusions. Generalizing this to the entire population of cars/owners is not perfect but is the best data that we have. GM is the only one who knows the true failure rate - ask them at the next BG event.
2. I'll stipulate that the CF user group represents a more aggressive group of drivers vs. those that do not post. Not bad drivers, just more likely to test the safety factor of the engine.
If this is true, then there is no doubt some sampling error in that we may be overestimating the true failure rate.3. At this point, we'll have to make an educated guess with respect to the true failure rate. Since people are more likely to post when problems arise, let's assume that they wil post it here if they aware of this site or are a member. Let's assume that, conservatively, 10% of the Z06 community posts or is capable of posting here. Then we have ~8 failures out of 2500 or so cars let's round to 10/2500 for simplicity. Now we have a failure rate of 0.4%. This probably over-represents the true failure rate but is the best we can do....
4. Others have posted that there is a problem with this engine that is being ignored. Yes and no. QS's methods (to reject those cars with modified tires or suspension) in one sense ingore the oiling issue as they would tend to mask this problem. However, since GM did not design the car to operate with coilovers or tires meant to add grip on the track, he is just simplifying the analysis as he wants to know how likely a stock car is to fail. This does not imply or prove there is not a "problem" with the LS7 - clearly it has some weaknesses such as the oiling system and, in an isolated group of units, bad rocker arms... However, people get really caught up in the N=1 problem - they read a few cases online and assume that every LS7 is failing or has some fundamental design flaw that will lead to a majority of LS7's failing under normal operation- this is not true.
Thank you so much for explaining that better than I ever could.
Part of the idea was to give the forum membership a number, the number of totally stock failures described in here so that people will have a number to work with .
This way they can decide on their own whether or not its time to panic......instead of being told by the ill informed and doomsayers that it is time for them to panic.
Knowing how many in here failed bone stock, they can draw their own conclusions.
07-30-2009, 12:14 PM
#83
Race Director
To get a more accurate number you might consider using the ratio of members on the forum with Z06's vs blown engines..
This would give us a better sampling of the data and % failure rates - however still flawed..
but good work!
This would give us a better sampling of the data and % failure rates - however still flawed..
but good work!
07-30-2009, 01:10 PM
#85
Melting Slicks
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Wow...this thread grew fast. Not in the mood to read all the pages but....
Nice try and EFFORT but it's kinda pointless
1) Compare blown with the number on z06 owners that are active on the forum.
2) You wont consider non-OEM tires and suspension mods. Are you saying our Z06 can't handle such mods that are not engine related? That's giving a bad image to the Z06.
Anyways, have fun with the thread.
Nice try and EFFORT but it's kinda pointless
1) Compare blown with the number on z06 owners that are active on the forum.
2) You wont consider non-OEM tires and suspension mods. Are you saying our Z06 can't handle such mods that are not engine related? That's giving a bad image to the Z06.
Anyways, have fun with the thread.
07-30-2009, 01:24 PM
#86
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I laugh at the origins of this research. Cause it isn't statistically accurate.
I've posted several times that my '06 motor blew in '06
At that time 5 of us members had motors give way.
And most won't post about it. And not everyone comes here.
The failure rate is more higher than 0.35% if I read ithat right.
I've posted several times that my '06 motor blew in '06
At that time 5 of us members had motors give way.
And most won't post about it. And not everyone comes here.
The failure rate is more higher than 0.35% if I read ithat right.
07-30-2009, 01:28 PM
#87
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QS:
4. Others have posted that there is a problem with this engine that is being ignored. Yes and no. QS's methods (to reject those cars with modified tires or suspension) in one sense ingore the oiling issue as they would tend to mask this problem. However, since GM did not design the car to operate with coilovers or tires meant to add grip on the track, he is just simplifying the analysis as he wants to know how likely a stock car is to fail. This does not imply or prove there is not a "problem" with the LS7 - clearly it has some weaknesses such as the oiling system and, in an isolated group of units, bad rocker arms... However, people get really caught up in the N=1 problem - they read a few cases online and assume that every LS7 is failing or has some fundamental design flaw that will lead to a majority of LS7's failing under normal operation- this is not true.
4. Others have posted that there is a problem with this engine that is being ignored. Yes and no. QS's methods (to reject those cars with modified tires or suspension) in one sense ingore the oiling issue as they would tend to mask this problem. However, since GM did not design the car to operate with coilovers or tires meant to add grip on the track, he is just simplifying the analysis as he wants to know how likely a stock car is to fail. This does not imply or prove there is not a "problem" with the LS7 - clearly it has some weaknesses such as the oiling system and, in an isolated group of units, bad rocker arms... However, people get really caught up in the N=1 problem - they read a few cases online and assume that every LS7 is failing or has some fundamental design flaw that will lead to a majority of LS7's failing under normal operation- this is not true.
07-30-2009, 01:57 PM
#89
Safety Car
^ I agree...although, sometime, even though we are talking 0.25 extra g, if it's already boarder line, that might just be enough to get it past that and it becomes a problem...so it is on a very fine line and people just need to be aware of that so they can take proper precautions...
07-30-2009, 02:15 PM
#90
Le Mans Master
This is fun. I will add the following assertions:
1. There are NO LS7 failures in cars that have never exceeded 85mph.
2. There are NO LS7 failures in cars that have never had the gas tank refilled.
3. There are NO LS7 failures in cars that have turned neither right nor left.
I encourage additions to my list . . .
1. There are NO LS7 failures in cars that have never exceeded 85mph.
2. There are NO LS7 failures in cars that have never had the gas tank refilled.
3. There are NO LS7 failures in cars that have turned neither right nor left.
I encourage additions to my list . . .
07-30-2009, 02:21 PM
#91
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This is fun. I will add the following assertions:
1. There are NO LS7 failures in cars that have never exceeded 85mph.
2. There are NO LS7 failures in cars that have never had the gas tank refilled.
3. There are NO LS7 failures in cars that have turned neither right nor left.
I encourage additions to my list . . .
1. There are NO LS7 failures in cars that have never exceeded 85mph.
2. There are NO LS7 failures in cars that have never had the gas tank refilled.
3. There are NO LS7 failures in cars that have turned neither right nor left.
I encourage additions to my list . . .
4. There are NO LS7 failures in cars with air in the tires.
07-30-2009, 02:53 PM
#92
Team Owner
Thread Starter
T h
The problem with this "data" is that hardly anybody takes their Z to the track in "bone stock" configuration. By stating that you don't want to consider cars that aren't "bone stock" what you're really doing is removing all Z's that are taken to the track. By considering only those cars that are driven easily on the street, of course you're going to be able to convince yourself that the Z06 has nothing wrong with it.
Saying that coilovers and/or tires are what cause these cars to fail is, IMO, just a cop out people use to convince themselves that there's nothing actually wrong with the design of this car. In reality, all the usual suspension and tire mods just don't really add *that* much additional stress to the oiling system of the car. The difference between a "bone stock" car and a fully modified car is about 0.2g to 0.25g at best.
Hell my car most likely failed due to a dropped valve, and there's no way that was caused by using better tires or shocks. But of course you don't want to consider my case in your study. The fact is you've just given a text book example of how to bias your data to provide you with the conclusion you expect/want to see.
Saying that coilovers and/or tires are what cause these cars to fail is, IMO, just a cop out people use to convince themselves that there's nothing actually wrong with the design of this car. In reality, all the usual suspension and tire mods just don't really add *that* much additional stress to the oiling system of the car. The difference between a "bone stock" car and a fully modified car is about 0.2g to 0.25g at best.
Hell my car most likely failed due to a dropped valve, and there's no way that was caused by using better tires or shocks. But of course you don't want to consider my case in your study. The fact is you've just given a text book example of how to bias your data to provide you with the conclusion you expect/want to see.
For whatever reason, this does not sit well with those who insis that the engine is "flawed" because of their experienced failures in their modified cars.
I wonder what would have happened had I located 30 instances of bone stock failures, or even 25.
I tend to believe that those attacking the thread and the result, would have been a lot happier.
But the numbers just don't fall that way.
The fact is that over a near 4 year time frame,there have been very few reported cases on this forum.
The numbers are what they are.
07-30-2009, 03:18 PM
#93
Melting Slicks
Look folks the reality of the Z06 dry sump system is is was never designed to alleviate oil pickup starvation in continuous high G turns at a race track. Anyone who has a clue can tell you a dry sump system with one scavenge section is there only to a. allow the motor to be lower in the car and b. to cut down on the oil windage and possibly pick up a little horsepower. This is just fine for street driven cars which is what a Z06 was designed for.
Dry sump systems that are really designed to ensure oil pickup under most all cornering conditions have multiple scavenge sections and multiple pick up points. Look at any race system. Some have up to 5 scavenge sections with multiple pickup points dedicated one to each scavenge section. Why so many scavenge sections? Simple they allow one or more pickup points to be sucking air while other pick up oil. A single section with it's input plumbed to several pick up points doesn't do you any good as when one pick up point uncovers it sucks air, reducing or eliminating the pumps ability to pick up anything. That's why real race dry sump systems have several independent scavenge sections. If you don't believe this you can see it for yourself if you have any kind of pump. Just make a Y connection to the pump with one leg in the liquid and the other leg in the air. Unless you have a high head type pump, which dry sump scavenge sections are not, you will notice a large decrease or total elimination of the pump function vs both lines in the liquid.
All this bitching about the oil system being defective is idle chatter by people who don't understand much about how a dry sump system operates and how it has to be designed if it is to ensure oil pickup under all loading conditions. The current system does what it's design intended. Lower the engine and reduce oil windage. Anything else is iffy at best.
Should GM make a foolproof system? I think not. Most people drive the cars on the street and the current system is just fine. If you want to go to the track there are several options to ensure proper oiling depending on how fast (what G load) you put on the oil.
Expecting GM to build in cost for the small minority who want to run HPDE's is foolish. Those people can make their own modifications. It does kind of suck that the very oil system modifications that will keep the engine alive may void your warranty but on the other hand if done properly you shouldn't have to use the warranty for oil starvation problems anyway.
For the purpose I bought a Z06, a street driven car, the current oiling system is just fine. I've had all kinds of race cars over the years and no stock passenger car does anything for me at a track.
I guess I'm performance spoiled.
Dry sump systems that are really designed to ensure oil pickup under most all cornering conditions have multiple scavenge sections and multiple pick up points. Look at any race system. Some have up to 5 scavenge sections with multiple pickup points dedicated one to each scavenge section. Why so many scavenge sections? Simple they allow one or more pickup points to be sucking air while other pick up oil. A single section with it's input plumbed to several pick up points doesn't do you any good as when one pick up point uncovers it sucks air, reducing or eliminating the pumps ability to pick up anything. That's why real race dry sump systems have several independent scavenge sections. If you don't believe this you can see it for yourself if you have any kind of pump. Just make a Y connection to the pump with one leg in the liquid and the other leg in the air. Unless you have a high head type pump, which dry sump scavenge sections are not, you will notice a large decrease or total elimination of the pump function vs both lines in the liquid.
All this bitching about the oil system being defective is idle chatter by people who don't understand much about how a dry sump system operates and how it has to be designed if it is to ensure oil pickup under all loading conditions. The current system does what it's design intended. Lower the engine and reduce oil windage. Anything else is iffy at best.
Should GM make a foolproof system? I think not. Most people drive the cars on the street and the current system is just fine. If you want to go to the track there are several options to ensure proper oiling depending on how fast (what G load) you put on the oil.
Expecting GM to build in cost for the small minority who want to run HPDE's is foolish. Those people can make their own modifications. It does kind of suck that the very oil system modifications that will keep the engine alive may void your warranty but on the other hand if done properly you shouldn't have to use the warranty for oil starvation problems anyway.
For the purpose I bought a Z06, a street driven car, the current oiling system is just fine. I've had all kinds of race cars over the years and no stock passenger car does anything for me at a track.
I guess I'm performance spoiled.
07-30-2009, 03:45 PM
#94
Melting Slicks
Member Since: Jan 2007
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The problem with this "data" is that hardly anybody takes their Z to the track in "bone stock" configuration. By stating that you don't want to consider cars that aren't "bone stock" what you're really doing is removing all Z's that are taken to the track. By considering only those cars that are driven easily on the street, of course you're going to be able to convince yourself that the Z06 has nothing wrong with it.
Saying that coilovers and/or tires are what cause these cars to fail is, IMO, just a cop out people use to convince themselves that there's nothing actually wrong with the design of this car. In reality, all the usual suspension and tire mods just don't really add *that* much additional stress to the oiling system of the car. The difference between a "bone stock" car and a fully modified car is about 0.2g to 0.25g at best.
Hell my car most likely failed due to a dropped valve, and there's no way that was caused by using better tires or shocks. But of course you don't want to consider my case in your study. The fact is you've just given a text book example of how to bias your data to provide you with the conclusion you expect/want to see.
Saying that coilovers and/or tires are what cause these cars to fail is, IMO, just a cop out people use to convince themselves that there's nothing actually wrong with the design of this car. In reality, all the usual suspension and tire mods just don't really add *that* much additional stress to the oiling system of the car. The difference between a "bone stock" car and a fully modified car is about 0.2g to 0.25g at best.
Hell my car most likely failed due to a dropped valve, and there's no way that was caused by using better tires or shocks. But of course you don't want to consider my case in your study. The fact is you've just given a text book example of how to bias your data to provide you with the conclusion you expect/want to see.
This is fun. I will add the following assertions:
1. There are NO LS7 failures in cars that have never exceeded 85mph.
2. There are NO LS7 failures in cars that have never had the gas tank refilled.
3. There are NO LS7 failures in cars that have turned neither right nor left.
I encourage additions to my list . . .
1. There are NO LS7 failures in cars that have never exceeded 85mph.
2. There are NO LS7 failures in cars that have never had the gas tank refilled.
3. There are NO LS7 failures in cars that have turned neither right nor left.
I encourage additions to my list . . .
There are NO LS7 failures with your typical vette owner..I mean with garage queens
Th e data gathered fails to support the notion that stock LS7 engine failure is common on this forum.
For whatever reason, this does not sit well with those who insis that the engine is "flawed" because of their experienced failures in their modified cars.
I wonder what would have happened had I located 30 instances of bone stock failures, or even 25.
I tend to believe that those attacking the thread and the result, would have been a lot happier.
But the numbers just don't fall that way.
The fact is that over a near 4 year time frame,there have been very few reported cases on this forum.
The numbers are what they are.
For whatever reason, this does not sit well with those who insis that the engine is "flawed" because of their experienced failures in their modified cars.
I wonder what would have happened had I located 30 instances of bone stock failures, or even 25.
I tend to believe that those attacking the thread and the result, would have been a lot happier.
But the numbers just don't fall that way.
The fact is that over a near 4 year time frame,there have been very few reported cases on this forum.
The numbers are what they are.
.....try again
07-30-2009, 03:47 PM
#95
Pro
Expecting GM to build in cost for the small minority who want to run HPDE's is foolish. Those people can make their own modifications. It does kind of suck that the very oil system modifications that will keep the engine alive may void your warranty but on the other hand if done properly you shouldn't have to use the warranty for oil starvation problems anyway.
.
07-30-2009, 04:00 PM
#96
Melting Slicks
Member Since: Jan 2007
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This thread is funny or should I same some of you guys on the forum..
First you guys bash Z06 owners who like to drive their 505 HP fast on the roads... You say take it to the track...
ok....
Next day your average job takes the z06 to the track, he's all excited thinking he got the hp monster out of all the cars, does 5/10 or even 7/10 on the track, half way through the lap, parts of his motors is all over the road and the rear catches on fire...guess what he at least he goes home with some of his motor in a cardboard box
Z06 owner is like WTF...you guys say...ummm you tracked the car, what do you expect? The Z06 is not a track car? Send it to our favorite sponsored vendor and upgrade it for another $20-30k...ya you guys know who and their followers
so others are like skip that idea...I will just have some fun on the streets.... but then hey, the car doesn't handle as well as a porsche or a GTR....some of you guys say that's b.s... just put on some sticker tires and some suspension mods....two days later and some millage the car takes a dump and then somebody comes up with the idea that of course the engine is going to blow because of those mods...
you guys get my drift....
Conclusion... there is a small percentage of these motors that have issues. But guess what, they are all the same common issues... does anybody see a pattern.
I'm not putting down the Z06 just telling it how it is without the political b.s
My Z is my 401 plan...I just keep putting money in it every month modding it to enjoy it until the fun last. If I can't track my car or enjoy the beast under the hood... I am not going to keep it nor will I sell it 5 years later with 2k miles like a good percentage of the owners.
First you guys bash Z06 owners who like to drive their 505 HP fast on the roads... You say take it to the track...
ok....
Next day your average job takes the z06 to the track, he's all excited thinking he got the hp monster out of all the cars, does 5/10 or even 7/10 on the track, half way through the lap, parts of his motors is all over the road and the rear catches on fire...guess what he at least he goes home with some of his motor in a cardboard box
Z06 owner is like WTF...you guys say...ummm you tracked the car, what do you expect? The Z06 is not a track car? Send it to our favorite sponsored vendor and upgrade it for another $20-30k...ya you guys know who and their followers
so others are like skip that idea...I will just have some fun on the streets.... but then hey, the car doesn't handle as well as a porsche or a GTR....some of you guys say that's b.s... just put on some sticker tires and some suspension mods....two days later and some millage the car takes a dump and then somebody comes up with the idea that of course the engine is going to blow because of those mods...
you guys get my drift....
Conclusion... there is a small percentage of these motors that have issues. But guess what, they are all the same common issues... does anybody see a pattern.
I'm not putting down the Z06 just telling it how it is without the political b.s
My Z is my 401 plan...I just keep putting money in it every month modding it to enjoy it until the fun last. If I can't track my car or enjoy the beast under the hood... I am not going to keep it nor will I sell it 5 years later with 2k miles like a good percentage of the owners.
07-30-2009, 04:18 PM
#97
Melting Slicks
This concept really cuts down the number of "stock" Z's being counted. Anyone who goes to the track more than once or maybe twice is going to have something other than runflat tires when they go to the track the next time. While I can see that slicks will potentially increase the G's around the corner, thus taxing the oiling system's capacity to function properly, I'm not so sure that a 100 tread wear indexed DOT tire will have the same significant effect. Another point - I believe the wear that causes the engine to blow due to oil starvation is cumulative (not sudden), so the number of new cases may increase at an increasing rate - we might be seeing that right now.
07-30-2009, 04:59 PM
#98
Le Mans Master
Look folks the reality of the Z06 dry sump system is is was never designed to alleviate oil pickup starvation in continuous high G turns at a race track. Anyone who has a clue can tell you a dry sump system with one scavenge section is there only to a. allow the motor to be lower in the car and b. to cut down on the oil windage and possibly pick up a little horsepower. This is just fine for street driven cars which is what a Z06 was designed for.
Dry sump systems that are really designed to ensure oil pickup under most all cornering conditions have multiple scavenge sections and multiple pick up points. Look at any race system. Some have up to 5 scavenge sections with multiple pickup points dedicated one to each scavenge section. Why so many scavenge sections? Simple they allow one or more pickup points to be sucking air while other pick up oil. A single section with it's input plumbed to several pick up points doesn't do you any good as when one pick up point uncovers it sucks air, reducing or eliminating the pumps ability to pick up anything. That's why real race dry sump systems have several independent scavenge sections. If you don't believe this you can see it for yourself if you have any kind of pump. Just make a Y connection to the pump with one leg in the liquid and the other leg in the air. Unless you have a high head type pump, which dry sump scavenge sections are not, you will notice a large decrease or total elimination of the pump function vs both lines in the liquid.
All this bitching about the oil system being defective is idle chatter by people who don't understand much about how a dry sump system operates and how it has to be designed if it is to ensure oil pickup under all loading conditions. The current system does what it's design intended. Lower the engine and reduce oil windage. Anything else is iffy at best.
Should GM make a foolproof system? I think not. Most people drive the cars on the street and the current system is just fine. If you want to go to the track there are several options to ensure proper oiling depending on how fast (what G load) you put on the oil.
Expecting GM to build in cost for the small minority who want to run HPDE's is foolish. Those people can make their own modifications. It does kind of suck that the very oil system modifications that will keep the engine alive may void your warranty but on the other hand if done properly you shouldn't have to use the warranty for oil starvation problems anyway.
For the purpose I bought a Z06, a street driven car, the current oiling system is just fine. I've had all kinds of race cars over the years and no stock passenger car does anything for me at a track.
I guess I'm performance spoiled.
Dry sump systems that are really designed to ensure oil pickup under most all cornering conditions have multiple scavenge sections and multiple pick up points. Look at any race system. Some have up to 5 scavenge sections with multiple pickup points dedicated one to each scavenge section. Why so many scavenge sections? Simple they allow one or more pickup points to be sucking air while other pick up oil. A single section with it's input plumbed to several pick up points doesn't do you any good as when one pick up point uncovers it sucks air, reducing or eliminating the pumps ability to pick up anything. That's why real race dry sump systems have several independent scavenge sections. If you don't believe this you can see it for yourself if you have any kind of pump. Just make a Y connection to the pump with one leg in the liquid and the other leg in the air. Unless you have a high head type pump, which dry sump scavenge sections are not, you will notice a large decrease or total elimination of the pump function vs both lines in the liquid.
All this bitching about the oil system being defective is idle chatter by people who don't understand much about how a dry sump system operates and how it has to be designed if it is to ensure oil pickup under all loading conditions. The current system does what it's design intended. Lower the engine and reduce oil windage. Anything else is iffy at best.
Should GM make a foolproof system? I think not. Most people drive the cars on the street and the current system is just fine. If you want to go to the track there are several options to ensure proper oiling depending on how fast (what G load) you put on the oil.
Expecting GM to build in cost for the small minority who want to run HPDE's is foolish. Those people can make their own modifications. It does kind of suck that the very oil system modifications that will keep the engine alive may void your warranty but on the other hand if done properly you shouldn't have to use the warranty for oil starvation problems anyway.
For the purpose I bought a Z06, a street driven car, the current oiling system is just fine. I've had all kinds of race cars over the years and no stock passenger car does anything for me at a track.
I guess I'm performance spoiled.
Great and correct post!Jim
07-30-2009, 05:18 PM
#99
Melting Slicks
Member Since: Jan 2007
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Look folks the reality of the Z06 dry sump system is is was never designed to alleviate oil pickup starvation in continuous high G turns at a race track. Anyone who has a clue can tell you a dry sump system with one scavenge section is there only to a. allow the motor to be lower in the car and b. to cut down on the oil windage and possibly pick up a little horsepower. This is just fine for street driven cars which is what a Z06 was designed for.
Dry sump systems that are really designed to ensure oil pickup under most all cornering conditions have multiple scavenge sections and multiple pick up points. Look at any race system. Some have up to 5 scavenge sections with multiple pickup points dedicated one to each scavenge section. Why so many scavenge sections? Simple they allow one or more pickup points to be sucking air while other pick up oil. A single section with it's input plumbed to several pick up points doesn't do you any good as when one pick up point uncovers it sucks air, reducing or eliminating the pumps ability to pick up anything. That's why real race dry sump systems have several independent scavenge sections. If you don't believe this you can see it for yourself if you have any kind of pump. Just make a Y connection to the pump with one leg in the liquid and the other leg in the air. Unless you have a high head type pump, which dry sump scavenge sections are not, you will notice a large decrease or total elimination of the pump function vs both lines in the liquid.
All this bitching about the oil system being defective is idle chatter by people who don't understand much about how a dry sump system operates and how it has to be designed if it is to ensure oil pickup under all loading conditions. The current system does what it's design intended. Lower the engine and reduce oil windage. Anything else is iffy at best.
Should GM make a foolproof system? I think not. Most people drive the cars on the street and the current system is just fine. If you want to go to the track there are several options to ensure proper oiling depending on how fast (what G load) you put on the oil.
Expecting GM to build in cost for the small minority who want to run HPDE's is foolish. Those people can make their own modifications. It does kind of suck that the very oil system modifications that will keep the engine alive may void your warranty but on the other hand if done properly you shouldn't have to use the warranty for oil starvation problems anyway.
For the purpose I bought a Z06, a street driven car, the current oiling system is just fine. I've had all kinds of race cars over the years and no stock passenger car does anything for me at a track.
I guess I'm performance spoiled.
Dry sump systems that are really designed to ensure oil pickup under most all cornering conditions have multiple scavenge sections and multiple pick up points. Look at any race system. Some have up to 5 scavenge sections with multiple pickup points dedicated one to each scavenge section. Why so many scavenge sections? Simple they allow one or more pickup points to be sucking air while other pick up oil. A single section with it's input plumbed to several pick up points doesn't do you any good as when one pick up point uncovers it sucks air, reducing or eliminating the pumps ability to pick up anything. That's why real race dry sump systems have several independent scavenge sections. If you don't believe this you can see it for yourself if you have any kind of pump. Just make a Y connection to the pump with one leg in the liquid and the other leg in the air. Unless you have a high head type pump, which dry sump scavenge sections are not, you will notice a large decrease or total elimination of the pump function vs both lines in the liquid.
All this bitching about the oil system being defective is idle chatter by people who don't understand much about how a dry sump system operates and how it has to be designed if it is to ensure oil pickup under all loading conditions. The current system does what it's design intended. Lower the engine and reduce oil windage. Anything else is iffy at best.
Should GM make a foolproof system? I think not. Most people drive the cars on the street and the current system is just fine. If you want to go to the track there are several options to ensure proper oiling depending on how fast (what G load) you put on the oil.
Expecting GM to build in cost for the small minority who want to run HPDE's is foolish. Those people can make their own modifications. It does kind of suck that the very oil system modifications that will keep the engine alive may void your warranty but on the other hand if done properly you shouldn't have to use the warranty for oil starvation problems anyway.
For the purpose I bought a Z06, a street driven car, the current oiling system is just fine. I've had all kinds of race cars over the years and no stock passenger car does anything for me at a track.
I guess I'm performance spoiled.
As an auto enthusiast and like to be knowledgeable about cars when speaking to fellow enthusiast about our cars.
Let's say this scenario comes up. We are talking about cars and the guy wants to find a fun sports car that he can drive on the street and do 3-5 track events a year.
I tell him that the dry sump on the Z06 is not intended for prolonged g-forces on the track. Would other cars like a GT3, M3, Evo, STI, GTR, Viper, ect... be superior to the Z06? Assuming the car is kept stock and the guy doesn't want to have to worry about having issues?
To be honest. I think the Z06 is a bad *** track car for the track. It would be a shame to loose faith as a street/ event hdpe car.
Back to the HDPE issue. Let's admit that the majority of Z06 owners go to the track for fun. Maybe 5-7 events a year. 15-20 minute sessions. Maybe doing 8/10ths max if they are good. Do these guys really need a full on track car (tons of money invested) for their events? In reality there are probably just a few guys that are hardcore racers that require a track set up?
The last thing on my mind is what you said about the Z06 being adequate for a street car. Are we talking within the legal range?
If I were to open up the car more than half throttle in 2nd gear on the streets you bet I would be going sideways.
If I opened up the car in third gear I would be hitting triple digits enough..
I don't think I could legal enjoy the Z06 on the streets unless I drive it beyond 3/10.
So what kind of street driving do you mean for the Z06 to handle, since I assume the Z06 is not build to handle the average joes HDPE events as you seem to explain.
