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What is the definition of track capable anyway? Are there measurable parameters to define it? Time/distance at throttle% at a a given temp?
 

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That is a good question. Our "favorite competitor" throughout the years, Porsches will go to any track, on any hot and humid day and finish a one hour session -- regardless of whether it is driven by an amateur or a pro.

When the C7 Z06 was introduced on 1.13.14, when asked in a Q&A sessions with the media that day and right afterwards, GM said it would complete a typical race session. Interesting that when I was sitting the audience at the BASH just under four months later, after Tadge's PowerPoint presentation in the public Q&A, he was asked if the Z06 was track capable, and his response was that it would complete a typical 25 to 30 minute track session just fine. Two people sitting around me commented that the length of the track session was now cut in half compared to earlier Z06 presentations.

GM's problem IMO, is that they test their cars with the most capable test drivers, those a level of skill that can complete a one hour session (longer if the fuel were still in the tank), without any overheating -- for they are skilled pros whom have driven the cars for months and months, hundreds of track laps in just that Corvette version. Then you get someone with a lesser skill level, they consequently cause the temperatures the Corvettes to run hotter than the GM official test drivers.

As another member of the forum and I were talking last night, it would be a great idea before the ZR1 is publicly announced as track capable, to not have that statement be based on what Jim Mero, Alex MacDonald, Mark Reuss and the rest of the Corvette track test team can do, but to subject that car to track lap after track lap with drivers much less skilled, and have them test the ZR1 on a super hot, super humid days on several very difficult tracks. If non-pro drivers can run such sessions under those weather conditions, without overheating or the tendency to overheat, then that would be a reasonable time to talk about it as track capable.

If that can not be done, GM please stop talking about our Corvettes as track capable, OR, say that just like we test and constantly modify our C7.R's to make them better and better, for track competition your Corvette will need similar testing, development and enhancements.

The old motto, "under promise and over deliver."
 

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Regarding what you say regarding the Porsches under hot tracks temperatures John, I was last Friday at the Imola F1 track

imola track.jpg

Very hard track, flat and hilly... but fantastic!
Naturally I used my C7, one friend came with his C7 Z06 modified with all the cooling updates possible available by GM (all paid by himself !!), his brother who sold his C7 Z06 after 6 month (temps problems on track) and drives now a Porsche GT3 and my son with his atmo but modified S2000.

There were a lot of cars, mainly Porsches.
The temperature was very hot : 99-100 Farenheit degrees.
We had the same temperature last year in Monza and at this level, the engines, the tires...and the guys are extremly sollicited.

Well, at Imola last Friday, after 4-5 hard laps all the cars had their temperatures going upper and upper, mine was staying max. at 3/4 of the full gauge measurements (sorry I don't find the right words) and I was extremly satisfied to say that I didn't had any temp problem (600W ventilator installed)... But in the afternoon, the oil temp was going too high for me: 250 Farenheit degrees ! So my hard laps were not able to be more than 4 in a row + 1 lap to refresh and so on.
The Z06 of my friend had the same problem + water temp one.
My son's S2000 had water temps problems for the first time too.

That said, the Porsches were not able to run hard more than 3-4 laps too BEFORE TO GO IN LIMP MODE !!!!

Honestly, if we had not done a so long travel to the track with all the fees, we would choose to not track the cars in those conditions.
 

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Thanks Alain for some 'apples to apples' conditions and comparison outcomes. :eek:nthego:
 

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That is a good question. Our "favorite competitor" throughout the years, Porsches will go to any track, on any hot and humid day and finish a one hour session -- regardless of whether it is driven by an amateur or a pro.

When the C7 Z06 was introduced on 1.13.14, when asked in a Q&A sessions with the media that day and right afterwards, GM said it would complete a typical race session. Interesting that when I was sitting the audience at the BASH just under four months later, after Tadge's PowerPoint presentation in the public Q&A, he was asked if the Z06 was track capable, and his response was that it would complete a typical 25 to 30 minute track session just fine. Two people sitting around me commented that the length of the track session was now cut in half compared to earlier Z06 presentations.

GM's problem IMO, is that they test their cars with the most capable test drivers, those a level of skill that can complete a one hour session (longer if the fuel were still in the tank), without any overheating -- for they are skilled pros whom have driven the cars for months and months, hundreds of track laps in just that Corvette version. Then you get someone with a lesser skill level, they consequently cause the temperatures the Corvettes to run hotter than the GM official test drivers.

As another member of the forum and I were talking last night, it would be a great idea before the ZR1 is publicly announced as track capable, to not have that statement be based on what Jim Mero, Alex MacDonald, Mark Reuss and the rest of the Corvette track test team can do, but to subject that car to track lap after track lap with drivers much less skilled, and have them test the ZR1 on a super hot, super humid days on several very difficult tracks. If non-pro drivers can run such sessions under those weather conditions, without overheating or the tendency to overheat, then that would be a reasonable time to talk about it as track capable.

If that can not be done, GM please stop talking about our Corvettes as track capable, OR, say that just like we test and constantly modify our C7.R's to make them better and better, for track competition your Corvette will need similar testing, development and enhancements.

The old motto, "under promise and over deliver."
I don't see any solid ground for a law suit based on the 30 min "track time" GM statement and customers expectations. I do believe that 15 min is too little and I wouldn't be happy at GM but at the same time I would not expect it to run the 24 hrs of LeMans either. There was no "contractual" promise and the line is very blurry, it is all what we thought it would be based on assumptions and comparisons to other cars. The way I see it, the Z06 is "track capable" but less capable than other cars and we can complain and GM should fix it if they want to keep/gain customers but they owe nothing else to Z06 owners.

As for the marketing gimmicks or deception, the norm out there is "over promise and under deliver" for most products, "under promise and over deliver" means lost sales at least in the short term. I don't think any of us takes the face value of an add, we go out there and research regardless of what the manufacturer says, we know better than that.

Don't get me wrong, I'm not on GM side, I'm rooting for Z06 owners, you should get a better cooling system as a warranty item, but then again, is 1/2 hour going to fine, 1hr? We end up at the same question w/o clear line on the sand.
 

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I think that in the "C7 Z06 overheating problem" the MAIN thing to consider is UP TO WHAT WHAT EXTERIOR TEMPERATURE LEVEL can we expect to have no overheating ?

All depend of the exterior temperature (my post here upper is a good example) and I think that the "battle" with GM will mainly turn around that as it's the only way for them to find a way out.
 

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I don't see any solid ground for a law suit based on the 30 min "track time" GM statement and customers expectations. I do believe that 15 min is too little and I wouldn't be happy at GM but at the same time I would not expect it to run the 24 hrs of LeMans either. There was no "contractual" promise and the line is very blurry, it is all what we thought it would be based on assumptions and comparisons to other cars. The way I see it, the Z06 is "track capable" but less capable than other cars and we can complain and GM should fix it if they want to keep/gain customers but they owe nothing else to Z06 owners.

As for the marketing gimmicks or deception, the norm out there is "over promise and under deliver" for most products, "under promise and over deliver" means lost sales at least in the short term. I don't think any of us takes the face value of an add, we go out there and research regardless of what the manufacturer says, we know better than that.

Don't get me wrong, I'm not on GM side, I'm rooting for Z06 owners, you should get a better cooling system as a warranty item, but then again, is 1/2 hour going to fine, 1hr? We end up at the same question w/o clear line on the sand.
Well, I will say that I am on GM's side (being the GM fanboy that I am) but, for the good of GM itself, I want to see them make it right with those owners who are affected. I don't track mine, and I have never hit a situation which put me in limp mode. However, other owners have. GM needs to make them whole, which, in my mind, means at least to retrofit their cars for free with the hardware which was put in the 2017s.

If there was an accident where the car was in limp mode and that is what caused the wreck, then GM should make those affected whole in that case as well (but, as far as I know, that is just speculation of possible scenarios from the litigants, and it has never happened in real life).

So, to reiterate, although I am a GM fanboy who supports them, I do so because my expectations are very high of how they will treat people the right way.

I hope GM can settle with something which will truly help the customers and make them whole, but I still fear the class-action suit will benefit the lawyers more than anyone.
 
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I think that in the "C7 Z06 overheating problem" the MAIN thing to consider is UP TO WHAT WHAT EXTERIOR TEMPERATURE LEVEL can we expect to have no overheating ?

All depend of the exterior temperature (my post here upper is a good example) and I think that the "battle" with GM will mainly turn around that as it's the only way for them to find a way out.
I think it will overheat, it is just a matter of time and many other variables (not only outside temp). There may be a limiting low temp under which no overheating is possible with all other variables being controlled. A cooling system like that can be designed but I think it is impractical, imagine a car tested in the death valley, 100% throttle, no ram air flow, until it empties the tank. It is going to take aerospace superalloys and a very large/heavy heat exchanger...In the end you may have to settle for overheating at some point (a combination of variables).

Unless...and here it is an idea for GM...they retrofit your Z06's w/ the C7.R technology.
 

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I have a 15 ZO6 and have been reading about this issue for some time now. While at Spring Mountain I asked about this issue and asked Ron Fellows who happened to be in to welcome our class. the short answer is that they provide GM with lots of feed back to improve the cars. My own experience there is that the cars are not driven long or hard enough to affect them.

I have had an over 50 year career in civil aviation. I was an Aviation Safety Inspector in the Federal Aviation Administration and have seen the many ways aeronautical engineers deal with heat dissipation. One such method is a fuel/oil heat exchanger since there is about 400 degrees difference in flashpoint between the two fluids. It does not require air flow, can fit in any space and be made in any shape. Given the large oil capacity of the car it would make a great cooling medium.
 

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I have a 15 ZO6 and have been reading about this issue for some time now. While at Spring Mountain I asked about this issue and asked Ron Fellows who happened to be in to welcome our class. the short answer is that they provide GM with lots of feed back to improve the cars. My own experience there is that the cars are not driven long or hard enough to affect them.

I have had an over 50 year career in civil aviation. I was an Aviation Safety Inspector in the Federal Aviation Administration and have seen the many ways aeronautical engineers deal with heat dissipation. One such method is a fuel/oil heat exchanger since there is about 400 degrees difference in flashpoint between the two fluids. It does not require air flow, can fit in any space and be made in any shape. Given the large oil capacity of the car it would make a great cooling medium.
If my calculations are correct, at the engine operating temperature, the specific heat of 40% DEX-COOL + 60% water is at least two to three times that of motor oil, and the ratio continues to increase with increasing temperatures. That leads me to conclude that engine coolant is much better for cooling the engine than motor oil is.

If that is correct, wouldn't the biggest bang for the buck be more engine coolant capacity, along with more airflow through the radiators to try to cool the engine coolant?
 

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You are correct, but one of the qualities and functions of oil, is as a heat dissipator. Fluid to fluid heat exchanging is very common. It is common in the aircraft industry to cool, skydrol, hydraulic fluids and engine oils with fuel. The answer to the overheating issue may have to come from several small things. The flashpoint of gasoline is -45 degrees F while 10W30 synthetic oil is +475 degrees F. This is hard to ignore and as I said earlier, it has long been used in aviation. Thanks for your comments.
 

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The problem w/ that is that the heat that the fuel will take away from the oil will travel back to the engine with the fuel, and the oil will get it back from the engine. The heat has to get out to the atmosphere somehow.
 

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You are correct, but one of the qualities and functions of oil, is as a heat dissipator. Fluid to fluid heat exchanging is very common. It is common in the aircraft industry to cool, skydrol, hydraulic fluids and engine oils with fuel. The answer to the overheating issue may have to come from several small things. The flashpoint of gasoline is -45 degrees F while 10W30 synthetic oil is +475 degrees F. This is hard to ignore and as I said earlier, it has long been used in aviation. Thanks for your comments.
You are correct. In military aerospace 32 years with the biggest on the planet. Water is not used. Cars---stone age technology used by comparison.
 

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Agree Busa Dave. Not to be dismissive of Manta's comment, I offer that the dissipation (transfer of heat/cold) is relative to the flash point. It is easier to cool the fuel with air than it is to cool the oil with air so passing the fuel through a finned tube will most likely cool the fuel before it reaches the injectors. Even the engine in my sailboat uses fluid to fluid for cooling. I still believe that it would be an elegant part of the solution to use fuel/oil heat exchanger to cool the engine. Thanks for your comments
 

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If that is correct, wouldn't the biggest bang for the buck be more engine coolant capacity, along with more airflow through the radiators to try to cool the engine coolant?
Look at the front end of the ZR1 prototypes we've seen photos of, and that appears to be exactly what GM has done.

Oh, and Corvette's already have liquid to liquid oil coolers. Oil to coolant, in fact. Perhaps both that cooler and the radiator need to be larger.
 

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I have a 2015 Z06 and have no interest in the law suit. However, I would like to know if anyone has developed an aftermarket fix for
the overheating problem. Some where on a forum I saw a fix that included about a gallon more of coolant installed on the drivers side of
the engine compartment that looked like a factory fix for this problem. Has anyone else seen this?
Thanks

Ronnie
 

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I have a 2015 Z06 and have no interest in the law suit. However, I would like to know if anyone has developed an aftermarket fix for
the overheating problem. Some where on a forum I saw a fix that included about a gallon more of coolant installed on the drivers side of
the engine compartment that looked like a factory fix for this problem. Has anyone else seen this?
Thanks

Ronnie
This one? http://www.stingrayforums.com/forum/granatelli-motor-sports/13981-granatelli-z06-heat-exchanger-tanks-gp.html
 

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Originally posted by Elegant:
As another member of the forum and I were talking last night, it would be a great idea before the ZR1 is publicly announced as track capable, to not have that statement be based on what Jim Mero, Alex MacDonald, Mark Reuss and the rest of the Corvette track test team can do, but to subject that car to track lap after track lap with drivers much less skilled, and have them test the ZR1 on a super hot, super humid days on several very difficult tracks. If non-pro drivers can run such sessions under those weather conditions, without overheating or the tendency to overheat, then that would be a reasonable time to talk about it as track capable.


If I agree completely regarding the difficult tracks, I cannot be OK to say that any pro pilot will guarantee to GM that the car will reach lower temperatures that with non-pro drivers ! It's completely the reverse! Any pro driver will sollicitate the car and the engine a lot more and so will be able to reach the limp mode faster.

Only GM have all the datas and it's sure that they were not as good as expected but they (perhaps) trusted in the fact that no gentleman driver will be able to drive as hard as their pro pilots! Unfortunately, the overheating problem appeared also with the customers.

So we can say that it's extremely difficult to compare "apples to apples" when the marketing claims something.
Beside that, any car can run 3 hours on a track if not sollicited more than at 70-80%... :peaceful:
 
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