Questions for current Z06 owners who track their car
05-09-2016, 04:01 PM
#21
Tech Contributor
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Not sure I make the leap to bad paint, but give me the benefit of the doubt for a moment. I'm not talking about reduced power, I'm talking about heating.
Anything that causes a reduction/retarding of timing will cause increased heat (it's held in the chamber longer, basic reason why). So from there I ask "What could cause retarded timing", and the two culprits could be high IAT (post-blower) or detonation.
High IATs could be caused by bad intercooler fill. Under load at the track that could add up significantly. Same deal for the oil blowby - it causes major detonation (oil has an octane rating of about negative 100 or something) which will cause the computer to retard timing.
Driving around a track at WOT with retarded timing should, in my mind, really cause a heating problem. So I worked backwards from there based on reports of things, like improperly filled intercooler tanks, that we've seen.
Make sense?
Now if it were really the case I imagine someone with the Cosworth tools or other logging would have noticed high IATs or a lot of knock retard. I don't think anyone has said that yet (I stay out of the mega merge) so I'm not seriously advocating either of these very strongly, beyond "Just in case it turns out that way, mark me down for one of each".
Anything that causes a reduction/retarding of timing will cause increased heat (it's held in the chamber longer, basic reason why). So from there I ask "What could cause retarded timing", and the two culprits could be high IAT (post-blower) or detonation.
High IATs could be caused by bad intercooler fill. Under load at the track that could add up significantly. Same deal for the oil blowby - it causes major detonation (oil has an octane rating of about negative 100 or something) which will cause the computer to retard timing.
Driving around a track at WOT with retarded timing should, in my mind, really cause a heating problem. So I worked backwards from there based on reports of things, like improperly filled intercooler tanks, that we've seen.
Make sense?
Now if it were really the case I imagine someone with the Cosworth tools or other logging would have noticed high IATs or a lot of knock retard. I don't think anyone has said that yet (I stay out of the mega merge) so I'm not seriously advocating either of these very strongly, beyond "Just in case it turns out that way, mark me down for one of each".
Bill
05-09-2016, 05:58 PM
#22
I do not own a C7, but from what I have read shifting below 6000 RPMs will take care of 90% of your problem. I think there is less penalty doing this with the Z06 because of the large drop in torque at high RPMs.
05-09-2016, 09:25 PM
#23
At VIR my best time is a 2:10 and I have been running a fair number of 2:11s when traffic isn't making me slower. However, Poor-Sha has turned a 1:59 and probably runs a consistent 10 to 12 seconds faster than I do. I have watched his videos and I am never going to get near him although I think I can get into the 2:08s. If he isn't getting overheating then there is hope for the rest of us.
Bill
Bill
05-09-2016, 10:58 PM
#24
Drifting
Member Since: Feb 2015
Location: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
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Poor Shaw, a 1.59 is flippin fast! My buddies that run VIR tell me that oddly enough Watkins Glen laps times are the same. A good friend with a supercharged C6Z full race car no street and great driver does 2.09's. Vintage GT1 race cars run in the high 1:50s at the Glen where you are, wow! No substitute for experience. Come up and play with us!
My 2015, Z07, M7 built Jan 15 has never overheated or come very close. It does have a few minor cooling mods and always track prepped 100%. I am fairly new to road racing with much more NASCAR oval experience but would say a 8/10ths driver. Like others have said a big difference in heat generation comes from not twisting the sheetz out of these. Shifting in the 4k to 6k range more often will be your friend.
Go for it
My 2015, Z07, M7 built Jan 15 has never overheated or come very close. It does have a few minor cooling mods and always track prepped 100%. I am fairly new to road racing with much more NASCAR oval experience but would say a 8/10ths driver. Like others have said a big difference in heat generation comes from not twisting the sheetz out of these. Shifting in the 4k to 6k range more often will be your friend.
Go for it
05-10-2016, 09:52 PM
#25
Intermediate
Thread Starter
Thanks to everyone who shared useful information to this post. I decided to go ahead and get a Z06 M7 and hope for the best. If I have any problems on track, I will cross that bridge when I get to it. It sounds like there are a least a few modifications that may improve the situation if it surfaces. I am not holding my breath that GM will ever offer a retrofit or even openly admit that there is a genuine problem. I have owned enough cars to realize that there is no perfect "production" car fresh off the showroom and most of the time you have to do stuff to them to make them track-able.
I do appreciate the guys on this forum who are exploring possible fixes and sharing their data and innovations with the rest of us.
I do appreciate the guys on this forum who are exploring possible fixes and sharing their data and innovations with the rest of us.
05-10-2016, 10:01 PM
#26
Melting Slicks
Ordered or purchased off the lot? Have it yet?
05-16-2016, 05:22 PM
#28
Lowering vs Heating
Anybody thought about a correlation between lowering on stock bolts (i.e., changing airflow from that designed by the engineers) and problems with engine, power steering, transmission heat problems? I haven't caught any discussion on this?
That being said I hope that lowering doesn't make things worse as I'm hating the height of my C7 SUV .....
That being said I hope that lowering doesn't make things worse as I'm hating the height of my C7 SUV .....
05-16-2016, 06:26 PM
#29
Drifting
Member Since: Feb 2015
Location: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
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Anybody thought about a correlation between lowering on stock bolts (i.e., changing airflow from that designed by the engineers) and problems with engine, power steering, transmission heat problems? I haven't caught any discussion on this?
That being said I hope that lowering doesn't make things worse as I'm hating the height of my C7 SUV .....
That being said I hope that lowering doesn't make things worse as I'm hating the height of my C7 SUV .....
05-16-2016, 06:53 PM
#30
Safety Car
After reading multiple posts regarding the overheating issue with Z06 cars on the track I would like to conduct a poll from those owners who have driven their car at the track:
1) Manual (M7) or Auto (A8) transmission
2) What model year is your car? 2015 or 2016 (include month of build if possible)
3) Has your car overheated at the track? If so, what was ambient temperature when it happened?
The reason I am asking these questions is because I am trying to find a common denominator if possible as to why this is happening. I know it is a real problem, but given that they have built almost 10,000 of these cars or more I would like to know how common it really is.
I own a 2008 Z06 which I track and am trying to decide if I should get a C7 Z51 vs. Grand Sport vs Z06 since I will be tracking the new car as well. After reading the overheating posts, I am thinking that most of the issues are with 2015 models with Auto transmissions and hot days. I am planning to get a M7 Z06 and track it in spring or fall and hoping that it won't be an issue for me.
Please don't reply unless you actually track your car. I am not interested in anecdotal stories about what you have heard or seen at your last track days. I drove at NCM and Barber in the last 2 months and it seems that the handful of C7 Z06's that were running had no issues.
1) Manual (M7) or Auto (A8) transmission
2) What model year is your car? 2015 or 2016 (include month of build if possible)
3) Has your car overheated at the track? If so, what was ambient temperature when it happened?
The reason I am asking these questions is because I am trying to find a common denominator if possible as to why this is happening. I know it is a real problem, but given that they have built almost 10,000 of these cars or more I would like to know how common it really is.
I own a 2008 Z06 which I track and am trying to decide if I should get a C7 Z51 vs. Grand Sport vs Z06 since I will be tracking the new car as well. After reading the overheating posts, I am thinking that most of the issues are with 2015 models with Auto transmissions and hot days. I am planning to get a M7 Z06 and track it in spring or fall and hoping that it won't be an issue for me.
Please don't reply unless you actually track your car. I am not interested in anecdotal stories about what you have heard or seen at your last track days. I drove at NCM and Barber in the last 2 months and it seems that the handful of C7 Z06's that were running had no issues.
November 2014
Overheated in mid 80* ambients: powersteering and coolant multiple times
I don't think you should do a poll. There is way too much bad advice on forums. I suggest you just think it through. There are about half a dozen reports of overheating in the media that you can verify. There is one radiator core stock, about the size you'll find in an entry level sedan stuck behind a full size intercooler core. That is the only air/fluid heat exchanger for both coolant and oil. Ron Fellows with GM developed a secondary radiator just to get the Stingray to run cool.
05-16-2016, 08:40 PM
#31
Without going into detail.......I will just say, the OP is simply rolling the dice.
When I go to track days and see every Z that showed up is overheating, that is all I need to know. And I would suggest you get this vitally important information before purchasing......
If you are going to make this purchase, you deserve to know the truth about it and that can be vividly seen only at the track.....then and only then....... it will be very apparent who limps off......
Unless someone or some peeps is/are B/S'n, EVERY Z overheats on track unless proven otherwise.
If your running parade laps at WSIR in the > 1:37.xx range, maybe......
When I go to track days and see every Z that showed up is overheating, that is all I need to know. And I would suggest you get this vitally important information before purchasing......
If you are going to make this purchase, you deserve to know the truth about it and that can be vividly seen only at the track.....then and only then....... it will be very apparent who limps off......
Unless someone or some peeps is/are B/S'n, EVERY Z overheats on track unless proven otherwise.
If your running parade laps at WSIR in the > 1:37.xx range, maybe......
Last edited by DLC7; 05-16-2016 at 08:43 PM.
05-16-2016, 09:02 PM
#32
This is my feedback
https://www.corvetteforum.com/forums...cr-battle.html
Its worth mentioning that on this track day while neither my Z06 nor Excelsior motorsport Z06 came close to overheating, it was surprising that a naturally aspirated 2015 1LE Camaro's with track package were overheating with oil temp pass 310F while 4 second a lap slower than my Z06 and even 11 second a lap slower than excelsior motorsport Z06.
https://www.corvetteforum.com/forums...cr-battle.html
Its worth mentioning that on this track day while neither my Z06 nor Excelsior motorsport Z06 came close to overheating, it was surprising that a naturally aspirated 2015 1LE Camaro's with track package were overheating with oil temp pass 310F while 4 second a lap slower than my Z06 and even 11 second a lap slower than excelsior motorsport Z06.
05-16-2016, 09:58 PM
#35
Without going into detail.......I will just say, the OP is simply rolling the dice.
When I go to track days and see every Z that showed up is overheating, that is all I need to know. And I would suggest you get this vitally important information before purchasing......
If you are going to make this purchase, you deserve to know the truth about it and that can be vividly seen only at the track.....then and only then....... it will be very apparent who limps off......
Unless someone or some peeps is/are B/S'n, EVERY Z overheats on track unless proven otherwise.
If your running parade laps at WSIR in the > 1:37.xx range, maybe......
When I go to track days and see every Z that showed up is overheating, that is all I need to know. And I would suggest you get this vitally important information before purchasing......
If you are going to make this purchase, you deserve to know the truth about it and that can be vividly seen only at the track.....then and only then....... it will be very apparent who limps off......
Unless someone or some peeps is/are B/S'n, EVERY Z overheats on track unless proven otherwise.
If your running parade laps at WSIR in the > 1:37.xx range, maybe......
05-16-2016, 10:21 PM
#36
Intermediate
You can check my prior post from last year when my 2015 A8 overheated (engine oil temps 300) in 99 degree weather on a short road course (Wild Horse Pass east course) in AZ. Several weeks ago, I took my car to AZ Motorsports Park and it did not overheat. Temps started in the high 60's and went up to the low 80's by afternoon.
Used manual shifting. The track is longer and faster than the previous course with longer straights. Saw top speed of 121 mph.
Used manual shifting. The track is longer and faster than the previous course with longer straights. Saw top speed of 121 mph.
Last edited by JIAZZ06; 05-16-2016 at 10:22 PM.
05-16-2016, 10:46 PM
#37
Hyperbole? Really.........
The 238 page thread on overheating is hyperbole?
What this means essentially is everyone else is wrong, and since you don't overheat.....no one does..
The evidence says otherwise......
Furthermore......the instructors at SM give advice in an attempt to mitigate a known overheating issue.....
Are you saying they are wrong to? If you are than I sense an agenda here.....
Last edited by DLC7; 05-16-2016 at 10:49 PM.
05-17-2016, 06:36 AM
#38
Did I say that no C7Zs have overheated? Reread my posts. You made an overblown statement that EVERY C7Z overheats unless driven at parade laps. This is the kind of nonsense spewed on this forum that drives me nuts.
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05-17-2016, 06:58 AM
#39
Agreed. Show evidence of one M7 Z06 that has overheated with proper track prep and no other contributing mechanical issue. Tons of people are running great times with the M7 - but yes the A8 is likely to overheat when pushed hard at the track (until cooling enhancements are completed).
Last edited by schaibaa; 05-17-2016 at 06:59 AM.
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05-17-2016, 01:21 PM
#40
Intermediate
Thread Starter
Without going into detail.......I will just say, the OP is simply rolling the dice.
When I go to track days and see every Z that showed up is overheating, that is all I need to know. And I would suggest you get this vitally important information before purchasing......
If you are going to make this purchase, you deserve to know the truth about it and that can be vividly seen only at the track.....then and only then....... it will be very apparent who limps off......
Unless someone or some peeps is/are B/S'n, EVERY Z overheats on track unless proven otherwise.
If your running parade laps at WSIR in the > 1:37.xx range, maybe......
When I go to track days and see every Z that showed up is overheating, that is all I need to know. And I would suggest you get this vitally important information before purchasing......
If you are going to make this purchase, you deserve to know the truth about it and that can be vividly seen only at the track.....then and only then....... it will be very apparent who limps off......
Unless someone or some peeps is/are B/S'n, EVERY Z overheats on track unless proven otherwise.
If your running parade laps at WSIR in the > 1:37.xx range, maybe......
I was at National Corvette Museum track four weeks ago and there were at least 3 C7 Z06 running and none of them had an issue that weekend.
Do I believe these cars can be prone to overheat? Well, there have been reports that they do by many sources. No one is disputing that.
Can overheating be a preventable issue with a few minor modifications and / or steps to prep the car for track use? I believe it is, especially since there are plenty of guys driving these cars on the track without any problems.
Can track prepping the car guarantee that my new Z06 won't overheat at the track? Well, of course not, but the question I originally asked was so I could get information on how to minimize that risk.
I asked the question specifically to people who 1) Own a C7 Z06/and 2) actually drive it on the track because I really am not interested in anecdotal observations but rather factual data. Unfortunately, there are plenty of people on this forum who muddy the water by presenting opinions as facts.
When I first started doing DE events, I saw a 944 spin and or crash at every single event for at least 2 or 3 years. Did I come to the conclusion that 944's are unsafe cars and prone to crashing because a handful of the them did? Obviously not. But your statement that EVERY one of these cars will overheat unless you are doing parade laps will be filed as "opinion only". Show us the hard data, please.