energystar

I find it heard to believe that when GM's engineers did the testing etc. that they didn't see these problems...surly they must of did at least 3 consecutive laps while testing....I read that Chrysler's engineers did a 24 hour testing on the hellcat and saw that the temp. on their supercharger etc. was well within limits but I wonder if because the hemi they use is an iron block helps some and I wonder how they cool their supercharger etc...

augerdogger

The oil temp shut down my A8 Z06 2 1/2 laps around a 1.7 mile track. Ambient temperature was 84F with 18%Rh. I was paddle shifting at recommended shift points, 1 or 2 green/yellow shift lights, downshifting going into corners. Tranny and coolant temps were acceptable. Drove up to a local ski area and watched oil temp approach 280F while staying in D. No problem coming down from ski area. Oil temp normally runs 220-240F. Doing an HPDE this weekend and local temps at the track are forecasted at 94-95F, Rh is unknown but I would guess 20-30%. New card for PDR to record all this.

SouthernSon

Perhaps your experience is different from some others. A quick search of overheating for those three makes also returned owner complaints. Of course, Porsche has been working on their design for decades, and considering the cost, may not have as many incidents of overheating. One can still add additional coolers to the vette, as many of us have, and still have quite a sum less invested. Personally, I would not expect a 600+HP car to run all day at the track without some overheating problems unless there were some extensive upgrades.

SouthernSon

That is not good. Something needs to be checked for sure. My bottom sucking cooling air C5Z only got oil to 255 at the NCM MSP last Friday after 30 minute sprints. And I was using high revs, 420 HP at the rear and running R7's.

Snorman

GT-R's are at least as notorious for overheating the GR6 as Z06's are for high ECT temps. That's why there are $2500-3000 trans cooler options out there from vendors like HKS and Greddy.
https://www.corvetteforum.com/forums...post1590052413
Note the FMIC as well.

So you are 100% correct. Stock GT-R's (CBA or DBA) will not survive 20-30 minute sessions stock, especially with a driver that can routinely push cars to 10/10ths lap after lap. Claiming or at least insinuating otherwise is at least disingenuous. I would also doubt a stock GT-R will maintain engine oil temps in a safe range while stock.
S.

Minkster

Pretty much the same for C6Z Carbons and Z07's.

FitFam

I think the better question is, are the automotive mags and journalists overheating the GTR's, Vipers, 911 Turbo's or GT3's while doing a few hot laps? I haven't read an article where that has happened when doing the comparisons.

Snorman

Yeah, you can keep those.

Snorman

I don't know.
Because AFAIK, only MT has reported elevated oil temps at Road Atlanta with Pobst driving. Were there others that I missed?
My points about the GT-R stand. And IMO, if data from a source is unreliable at one facet, it is probably unreliable at all.
S.

FitFam

MT a few times now, Car and Driver overheated a C7 running up a mountain, I haven't seen anything else either. MT beats the crap out of every car they get and good on them for doing so, but they haven't overheated any other GM cars on the tracks they usually run the cars, including the ZL1 which is supercharged, at least what I have read.

I will never overheat the car or at least I don't think so but I do hope that the frequency will be less. I agree for those running 25-30mins track periods it can/could happen but certainly running a few laps or spirited runs shouldn't induce a car to overheat.

FitFam

btw I talked to guy today from a Dodge dealer that said they are seeing some heat issues from the Hellcats, I haven't run mine hard enough yet, but that engine also produces a lot of heat. The fans in my car were kicking in today driving around town...it was 30C

descartesfool

My GT-R is the oldest one made (2009) of the current generation. I have stated before that I had to add a secondary HKS transmission cooler and posted pictures of the HKS kit with all its laser cut stainless mounting brackets to show what a high end aftermarket parts supplier could provide, and cost was $1900 (depends on the yen value). I then added a secondary oil cooler to keep oil temps lower, although I never actually had an engine oil overheat condition, but I wanted lower temps. I can drive it at 10/10 ths all day and it never overeheats. The production a few years later increased the front radiator opening in the bumper and increased the size of coolant lines back to the transmission cooler, and it seems most people can run it hard all day on track without overheating and only some might need to add a transmission cooler but nothing else, often if they have boosted the power of the engine with aftermarket parts like I did (exhaust, intake and ECU tuning). So an old GT-R needs help to run all day, but it only costs $2000-$3000 and it makes the car completely bullet proof. My GT-R is 7 years old and has never had a repair of any kind, and I have done about a dozen track days a year with it for those seven years. When GM or other aftermarket guys come up with proper solutions to cool the C7 on track, that will be great. I am fed up with my transmission at 300 F every time I take my Vette to the track, and fed up with it's coolant temp overheat warnings, and fed up with its constant AFM actuator failures requiring a visit to the dealer every time I take it to the track, which I avoid now. GT-R is a much better track car than my Vette. Hopefully aftermarket parts will make the Vette an equally good track car, but I am tired of waiting and dealing with GM customer care and the GM brand quality manager. GM has no solution for my overheating Vette. Talked to my service manager yesterday and he is now suggesting moving to a GM buyback. I've never been in that situation before.


And as for mods on the Vette, the last 3 times my AFM actuators have failed the GM brand quality manager has made my service manager confirm with me that my Vette was not modified ( he says each time he is sorry but he has to ask), which I interpret to mean they are looking for a way to deny warranty coverage, as if anything I could be doing would cause those AFM actuators to fail. So not happy with my first ever purchase of an American car. Now considering cars that don't overheat on track, like the Viper and the GT3. Wish GM had properly engineered the car to live up to its marketing as the most track capable Corvette ever.

DLC7

Silence is deafening in here.


Specifically, after the last post?

GP1224

Yes the GTR track pack has overheated by magazines.

peterjank

Yes, I overheated the engine on my A8 Z06 while manually shifting. The data and video is available in this thread:https://www.corvetteforum.com/forums...imes-here.html
Please see the listings for peterjank in post #2 (The Tracks) under the Autobahn Country Club heading in the thread above.

Also, regarding the power steering overheating issue there may be a correlation with the use of A/C while on track, i.e. having A/C on may contribute to an overheat of power steering in some instances. However, the power steering has also overheated in some cases when A/C was not in use. I have only experienced my power steering overheating once and it happened to be the one time I accidently left the A/C on.

ACRucrazy

About 3 tanks of fuel and 200+ miles over the course of 2 days with no complaints. That was in between a 550 mile drive to the track and 550 mile drive home too. However one would say a 7 year old Viper is most likely archaic and not a highly tuned vehicle such as a C7Z.

augerdogger

I overheated the engine oil while manually shifting A8 with less than 7 minutes track time. I am doing an HPDE this weekend and will record everything with PDR. Engine oil is always warm, 210-230F, at freeway speeds and got it up to 280F driving up to ski area at 15-25 mph.

Deuuuce

There is clearly an issue, its undeniable. Most production cars during the WAJ media days go 3 laps at MRLS, switch drivers, then go another 3 for 2 hours in the morning, 3 hours in the afternoon and the only thing that gets hot or worn are the brakes. Hellcats, Viper GTS, GT-R, R8s, etc. etc.

Hirohawa

Motor Trend had 5 instances of overheating the Z06 - 3 different times by Randy Probst on a track, once around the figure 8 and once sitting in traffic. They also complained of massive heat from their other testing. This is all within 9 months. I've never seen that many issues with a new sports ever. Especially one in this price bracket.

I just don't see the point of arguing against the fact that there are real issues with the new Z06.

thebishman

Claude,

The transmissions in the C7 Z06 are not overheating, unlike the first couple of years of the GT-Rs. GM even held back production of the A8 models to add the secondary transmission oil cooler which has cured any c/o tranny overheat situations that I'm aware of.

Nissan absolutely did not do this before they released the 2009 GT-R here in the USA, and guys like you and I became beta testers for multiple cooling solutions so that we could run the GT-R reliably for 25-30 minutes at a decent rate around a road course. I had to back off a little even with the HKS tranny cooler to keep the engine oil below the 'red zone' which IIRC is around 300dF in the GT-R. You even had to add the secondary EOC to your car to maintain decent engine oil temps.

THAT is where we are with GM at this point in time: will GM step up and take care of those of us believing them when they called the C7 Z06 the most "track capable" Z ever and produce an add-on secondary EOC, or are we going to have to turn to the after-market. Just like owners of track driven GT-Rs had to do when those cars were first released to the public.

I know you're incredibly frustrated with the issues you've had with your Z51, but as someone who has owned both a 2009 GT-R and now a 2015 Z06, I certainly feel that the Z is so much closer to being 'track ready' this early in its lifespan than the GT-R ever was.

Bish