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Does anyone know how to contact the 2015 Corvette Z06 engineering division and get "official" answers to the question below?

The most pressing issue is a need to discuss the overheating issue on the track. Does GM have recommendations on how best to handle this?

Are there GM fixes planned? Can they be retrofitted?

Can we find 3rd parties to try and remedy this condition?

What will or will not void the warranty in trying to resolve the overheating issue?
 

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I don't think you will get any more than this response recently posted on another Corvette forum:

Question:
Does GM have any plan to sell a cooling pack in the future for the C7 chassis? Is it even a possibility, and if so, what would it look like?

Background
The limitations of the radiator and related parts that help the car stabilize oil and water/coolant temperature are easily reached when the C7 Z06 is driven aggressively (such as on a track at an HPDE event). There are now many reports from owners overheating the cars in 80 degree weather or even in 70 degree weather. This limitation of the car as sold will be exacerbated in the coming summer months. Many media outlets have reported overheating. This includes every occurrence when Motor Trend tested the C7 Z06 and during daily driving the C7 Stingray by Edmunds. See here:
http://www.edmunds.com/chevrolet/cor...tain-road.html

The commonly displayed overheating message is "Engine Overheating, A/C has been turned off, please idle engine." Coolant temperatures in particular quickly approach 257 degrees which prompt the computer to issue a warning in the center display.

Other manufacturers offer such an optional package to effectively cool the car. See for example the new Shelby GT350 Track Pack is described as follows: "optional with the Track Pack, an engine oil cooler and a transmission cooler."

https://media.ford.com/content/fordm...0-mustang.html
Quote:
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[TD="class: alt2"]Tadge answered:
I see the reference to both Stingray and Z06, so I will address both starting with the Stingray: We do all of our track validation with the front plate removed and I am not aware of a case of overheating when a Z51 car is properly prepared. The article referenced talks about cooling issues on the street when driven aggressively in hot temperatures with the front plate installed. I see in the picture of the Edmunds long term test, the car has a front plate in what we call the "show" position and so when driven very aggressively had insufficient cooling. As discussed in the owner's manual, this panel is "to be removed when driving aggressively or in hot weather". All cars shipped to states that require front plates also have a plate frame that mounts higher on the bumper and does not block as much of the cooling flow. Because states have varying height-to-ground requirements the plate holder sits high on the front bumper to accommodate those laws. While fully legal and beneficial for cooling performance, it doesn't look very good and many customers have asked for a more integrated solution, hence the optional "show" position centered on the grille. Although intended as a "show" position, for 99% of street usage the cooling performance is fine. Some may be quick to point out that other cars seem to be able to have low front plates and robust cooling (fourth and fifth generation Corvettes, for example), but those are "bottom breathers" with major compromises to down force performance. Although there are very few complaints from Z51 customers on cooling issues, we are looking at taking some of the learnings and hardware from the Z06 and making them available on the Stingray. For example, the front-mounted supplemental trans cooler developed for the Z06 automatic will be included in the Z51 package for automatic coupes starting in the 2016 model year.

We have discussed the Z06 cooling robustness in this space before and are very concerned about what some customers are experiencing. We have built over 8,000 Z06's so far with the vast majority of them having no cooling issues. We are working to gather data from customers (some of whom may have posted here) who have concerns and are in the process of sorting through that. We have found a few build issues, a few prep issues, and some vehicle mods that have hurt cooling performance. An example of a build issue would be an improper bleed of the intercooler circuit. Even a small air bubble can impact performance. As I indicated in in my last "Ask Tadge" answer, we design for 30 degrees centigrade and have for decades without customer dissatisfaction. We may have to move our target upwards since customers appear to want to run their cars very hard at elevated temperatures.

The question asks about what kind of cooling upgrade could be made available through GM performance parts. I can tell you we are looking at a variety of robustness improvements that could take many forms. It could be in calibration (and for followers of these threads, we haven't forgotten about the "rough track" chassis calibration talked about a few weeks back), cooling system or specification changes, or even super charger hardware tweaks. It will take us a while to work through what makes the most sense and to do the validation, but we will make every effort to make sure that the changes are backwards-compatible to vehicles already produced. In the meantime, we sincerely appreciate the customers we've contacted openness and willingness to work with us on continuous improvement.

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Tadge did not get asked, nor did he answer, the second question the OP posed about what additional aftermarket options are available, and will they void the warranty. While there is not an official GM response to that part of the question yet, have not yet seen anyone express the opinion that additional cooling capacity would void the warranty. Know that several aftermarket performance vendors are exploring such additional cooling capacity remedies.
 

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Tadge's comment that more than 8000 vehicles have been built with few overheating issues is sidetracking the issue in my opinion. I will assume that very few of the 8000 vehicles built have been put through a hard workout, mine included. The issue may materialize only under certain conditions but that doesn't mean it doesn't exist.
 

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Discussion Starter · #5 ·
I sincerely appreciate GM's effort to get to the bottom of the Z06 on track overheating issue. I have been doing high performance driving for 20 years including club racing. Needless to say I drive all cars hard on track. I would love to make my car available to GM to do a diagnostic to see if something is not quite right. I do not want to pursue any aftermarket solutions that would void my warranty and would rather do something ASAP that is a GM remedy.

I have another track event for 4 days at VIR in mid June. My approach is to drive the straights to redline, but keep the revs below 5,000 to 5,500 RPM in the twisties and rely on the low end torque to give me the competitive performance needed. Not a perfect solutions and may cost some time but it is better than being sidelned by an overheated engine in 3 or 4 laps.

Tadge, please work on this. The Z06 with the Z07 package is an awesome car and I really want to drive it the way your team designed it.
 

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As a soon to be recipient of a 2016 Z51 model, I am glad to hear that my car should be getting the supplemental transmission cooler from the Z06. That was one thing that I don't recall hearing in the list of changes between the 2015 and 2016 models.
 

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Same here, that is good news
 

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While attending Corvette driving school at Spring Mountain Ranch I asked the instructors about overheating issues with Z06 A8. The response was no issues as long as you use paddle shifting to avoid high engine revs. I have driving the track in D letting the computer select shifts and there are times it does stay in a lower gear causing high engine revs. Paddle shifting is the way to go for track driving to avoid high revs and manage heat.
 

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Hi, I am looking at a 2015 Z06 3LZ this weekend. It has only 4500 miles. I wanted to ask, are there issues (such as overheating / paint) with 2015 that were corrected in '16? Is the overheating issue common? I have a 2014 Stingray and LOVE it. It's Laguna Blue and so is this Z06. Any advice would be appreciated. Thx
 

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There are approximately 12,500 Z06's in owners hands and probably 99% have not had an overheating issue, and those that did were almost always on the track.

No issues with mine, nor anyone of my friends, even though we have driven ours on hot, hot days.
 

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The Z06 cooling system is more than adequate for street usage and will be sufficient for most skill levels on the track. Those at the upper end of the skill range will be able to overheat the Z06. For the M7 guys GM has an additional cooler which fits where the front A8 cooler is located. Several aftermarket companies have additional cooling options that will work with either transmission with various levels of complexity for the dedicated track rat.

I believe at some point in production some additional exhaust heat wrap was added in the area of the oil to coolant heat exchanger but that would be the only change from 2015 and could be easily added.

My order was accepted by GM last week so my Laguna blue should be ready for museum pickup sometime in April. With my driving skills at age 55 the only way I will overheat it is if a plastic bag gets stuck to the front grill :)
 

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Good info re the z06 cooling issues. I plan to order a z06 with z07 package in the near future with delivery expected to take about a year. I have heard from a very good source that Chevy is indeed coming up with enhancements to this cooling problem but will not be integrated into production until the 2017 model rolls out. Perhaps Tadge could kindly comment on this?
 

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Welcome to our forum Enz512tr and best of luck with your Z06 order!
 

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Enz512tr, welcome aboard. Maybe by the time the General builds your Z06 the issue will have been resolved. There are members attending the BG bash and the cooling issue would be an excellent question for the engineers.

SF
Rick
 

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Thanks. I plan to run the car at Mosport a few times each summer and don't want to experience overheating issues. Having driven the Zr1 at Spring Mountain on two occasions, I can recall the console had got so hot it could burn your right leg but I never experienced any loss of performance. Both times I attended, the outside temp was very hot. Hopefully GM can make the necessary improvements for the 2017 z06.
 

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I own a 2015 Z06 3LZ. It gets way to hot for my liking. I live in Fla. I've been on the track in it a few times and am paranoid about how hot the engine gets. I race other cars in the scca. I bought this car as a device to practice and get track time when I'm not racing. I paid a lot of $$ for it and must say I am disappointed. If it wasn't under warrantee, I'd figure out how to fix it myself.

I guess you live and learn.
Jimmy
 

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There's been a rumor for a while now that GM would add the Chevy Performance secondary radiator as standard for 2017s with the M7 - has any recent 2017 info confirmed this? M7 overheating is already infrequent, relative to the A8.
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Text Font Line Output device Furniture
Auto part Automotive fog light Automotive exterior Automotive window part Bumper

For the primary, there's always a Dewitts radiator: Corvette C7 Performance by WEAPON-X Motorsports ? Dewitts C7 Competition Radiator - I believe the LT1 and LT4 use the same primary radiator.
 
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I own a 2015 Z06 3LZ. It gets way to hot for my liking. I live in Fla. I've been on the track in it a few times and am paranoid about how hot the engine gets. I race other cars in the scca. I bought this car as a device to practice and get track time when I'm not racing. I paid a lot of $$ for it and must say I am disappointed. If it wasn't under warrantee, I'd figure out how to fix it myself.

I guess you live and learn.
Jimmy
He answered the question about the warranty as well on that forum. Basically, the additional coolers will not void the warranty, either. The only GM Performance Parts that won't be covered for a Z51 car are Z06 brakes and a suspension kit because those are for "track use only."



AliZ51 asked:
GM performance part group is finally on the move and we are hearing one announcement after another with regards to the release of new components. This is great until we read the disclaimer and that all these parts would/ will void the powertrain warranty. How can GM justify voiding a powertrain warranty even for a carbon fiber cover? Please clarify. Thank you.


Tadge answered:
Great question from the forum. Although I am not directly responsible for performance parts, this question caused detailed conversation about the relationship between that business activity and our factory warranty. That is why this answer took longer to provide. As we continue to develop more and better performance parts we will strive for better clarity on impact to warranty, if any.

We assume that this question originated from the new SEMA offerings of Performance Parts for Corvette (cooling kits, aero kits, carbon fiber braces, brake kits, T1 suspension kit, and driveline kits) and the publishing of these parts in the 2016 Performance Parts catalog. The warranty disclaimer statement that is published in the catalog (see statement below*) was originally written for crate engines and engine parts, and had not been changed to reflect the differences between Powertrain Parts and our Vehicle Performance Parts offerings. We are in process of re-writing this statement and will publish the update in the catalog and online at the next printing.

Our intent is not to altogether void the New Vehicle Limited Warranty nor the Powertrain Warranty on our Vehicle Performance Parts, and most of the Performance Parts available for Corvette do not restrict these warranties at all. We will, however, need to restrict some aspects of these warranties, as noted below, given that installation of some Performance Parts will alter the intended uses of the production vehicles. There are also instances where Performance Parts take the vehicle out of compliance for public road use. These restrictions will be disclosed to Performance Parts consumers so that they can knowledgeably choose whether or not to install such parts. .

In the first printing of the catalog, the following parts were called out with the standard warranty disclaimer. We are now more clearly defining the specific restrictions and will publish these in the next catalog update:

Secondary Radiator and 600w fan — this was a misprint in the catalog — there are no warranty restrictions on these parts. These will not void the New Vehicle Limited Warranty.

Carbon fiber braces — these parts are intended for off-road use only. Our long term, 10 year corrosion testing is not complete and therefore warranty claims for corrosion at the attachments of the brace to body will be restricted. The remainder of the factory warranty is intact.

Z51 brakes for Stingray — in this kit, the mass dampers were removed from the stock Z51 pads in order to fit inside of the base Stingray wheels. Mass dampers are used to tune the system for brake noise, and therefore this kit is not warranted for noise performance. The remainder of the factory warranty is intact.

Z06 brakes for Z51 — this application is for off-road use only because the stock Z51 wheels do not fit over the Z06 brakes. We cannot test or certify to all of the potential solutions. Any failures occurring as a result of the non-production wheels selected by the customer would not be covered. The remainder of the factory warranty is intact.

T1 suspension kit — this suspension kit is designed for off-road, racing use only. Generally speaking we expect vehicles equipped with the T1 content would also be outfitted with track slicks and raced, both of which do void the general vehicle warranty.

Thank you for bringing this issue to our attention. You have made us realize that a generic disclaimer does not clearly communicate the reasoning and intent behind each of the Performance Part restrictions. We are pushing to continue to bring new, exciting parts to market, and we’d love to hear your feedback.

*Current Catalog statement (for reference only):
The use of this engine or component in a new Chevrolet vehicle voids the vehicle powertrain warranty and may result in adversely affecting vehicle performance. In some cases, use of certain Chevrolet Performance components may result in the failure of other components or systems, thus voiding the warranty of the failed component or system. Chevrolet Performance components installed in new vehicles do retain their regular warranty coverage unless otherwise noted.

These engines and components have not been tested or validated by GM Engineering for use in these vehicles. Installation of components or engines in non-original applications may require fabrication or modifications that affect other vehicle systems. Certain engines may require modifications to the vehicle for fit and operation.

The installation and operation of these components or replacement engines in new vehicles is intended for off-road operation only.
 

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Has anyone added the Chevy Performance Secondary Radiator on 2015-16 Z06? If so, please share the results.

Thanks in advance,
Jimmy
 
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