Deuuuce

So it is engine oil temps, transmission oil temps, and coolant temps and any combination of the 3 for both A8 and M7 cars, but obviously not for everyone.

Need a spreadsheet to track the variations.

I look forward to hearing about a group of 3-5 and swapping cars.

SBC_and_a_stick

Some have claimed they got an oil overheat, but I haven't seen any PDR results showing oil in the overheating range. They may be confusing it with coolant overheat or perhaps they did get it but don't have PDR.

Coolant and powersteering overheat in both A8 and M7 cars. I've seen people with less than 10 track days do it so you don't really have to be a good driver.

JG853

I agree

How about adding a C6 Z06 to that list of cars that can be tracked stock as well.

JG853

Glad to hear you are not having problems. There seem to be a few of you out there in the minority. I know each car is different, but the cooling of these cars is not a variable factor, meaning the tolerances are basically the exact same... so that always leads me to ask how is it possible that a few are not having problems given the way was engineered for cooling?

thebishman

This kind of blanket statement is nonsense. I am a "competent" driver, and even though I had taken a break from the road course for the last five years, in my two track weekends thus far this year, I have easily been the fastest car in my run groups. I have never had to 'retire' the car early due to overheating issues as I'm 'competent' enough to know how to drive around the car's limitations; i.e. short shift to take advantage of the torque characteristics.

Granted my oil temps have been higher than I'd like, and I've never suffered a PS issue for which I thank you in part due to your modification that I adopted. But to state that everyone will have overheating issues at a >80dF ambient is simply untrue.

Bish

truth.b

A C6 manual Grand Sport Coupe can be added as well.

Mad Dog 24

I agree with Bish, not all cars have issues and those that do were most likely either not prepped correctly or have there own specific internal problem.

Our Z07 has been driven hard and twice by a "competent" driver (not me although I wish!) that is about to take his class championship at VIR. We have always been the leader of the pack in a given group. We have not overheated once or a steering failure, period! In fact the highest coolant temps we've seen were 232 and oil 261. Big tracks and tight tracks it does not matter. I am willing to bet there are more C7's tracked without overheating or other issues than do. We don't here from them, their out having so much dam fun!

FYI, Just changed our rear Diff fluid and it did not look good at 6,800. The magnet had a lot of metal on it the color was gun metal grey. If your tracking your car I suggest getting it changed. We will monitor ours next season and probably do it again in 5k.

SBC_and_a_stick

I agree that is a robust car for tracking, especially in Z07 trim. It's just that it's out of production, and when you buy used your miles may vary.

I didn't say everyone will have overheating issues. However, I've seen people with track days in single digits easily overheat the car. It's obvious an entry level driver can push it past the limits. Not all entry level drivers are equal. Obviously if you drive slow enough it won't overheat.

As you've stated, you drive slower to prevent overheating. Its not that the car is robust or that you are not a good driver, it doesn't overheat because you adjust your driving style to account for the car's deficiencies.

Correct me if I'm wrong but don't you have about half a dozen cooling mods on your car? Maybe its' your car that's different than others. What does your feedback have to do with a stock Z06? Do you propose that GM's manual says anywhere that the coolant mixture is 80% water, or that we should Mcgiver our underbody with metal stampings, or drill 3 inch holes in the front of the car?

rsilver

mad dog, you have done a lot of good mods that seem to help in your case. I have done them to my Z07 A8 also and no doubt they help but not a solution yet.I hope the cat shields help, have not got them yet and will be interesting to see if it helps the A8. (I know the current solution is paddle shifting) I think there are some guys out there that are overheating on the track but just don't post. The guy I met at High plains had a A8Z07 and overheated all summer there. He is a forum member, wrote some posts about overheating then got short on time, so no more posting. I bet there are a lot of guys like that, I am on the fence as this it taking way too much of my time but I hope over the winter more solutions come out and I can spend more time having fun.
As for diff fluid, Glad you mentioned the condition of your fluid.that makes it clear its something that needs attention.

rsalco

That is an inaccurate statement. Stock C6Z06's driven hard by experienced HPDE pilots will overheat. Even with the ZR rad [Z07 pkg.]. Many if not most track rats install race rads in the C6's to overcome this issue. It is one of the commonly recommended mods by the better race shops such as Phoenix Performance in Philly.

SBC_and_a_stick

This is one way to put into perspective the inadequacy of the C7 Z cooling system. Based on GM's own calculations, it removes just as much heat from the system as the C6 Z06 Z07 system. Based on what you just said, this system is inadequate to support n/a 505hp. The C7 Z raises the following challenges on top of the C6 Z application:

*intercooler that blocks the entire front side of the radiator
*an in-block 2,900 psi fuel pump
*an additonal 145hp and 180tq
*an additional 350lbs of weight
*shorter gearing (auto)
*stickier tire (more of the power can be put to use)
*wider tire (more of the power can be put to use)
*eLSD (more of the power can be put to use)
*more downforce (more of the power can be put to use)
*TVS blower (generates heat through friction, and requires an additional 65 hp to spin)

Mad Dog 24

SBC, For the record we have 4 cooling solutions we feel are helping. The 3 inch cooling duct direct to the oil cooler. The cat covers and the 90\10 water in the cooling system. The under body fresh air scoop to the steering actuator. If that's what works great but I think we need a bit more. If GM aint going to take care of something I will.

I've raced and had teams from snowmobiles, cars to boats for many years and some at high levels of competition. Never in even stock classes have we or anyone ever left anything "stock"! OMG you wouldn't last one round! Maybe its just me but I enjoy (to a point) making my stuff a bit better, faster, cooler and looking better than my competition and especially the factory boys.

On a positive subject to accomplish something here. We all have hot oil running in and out of our holding tanks behind the right front wheel. We thought if there is a way to keep that tank cool would also help drop the oil temps some. Its now encased in an area with little to no fresh air. The drag guys use cooling tanks with ice for similar issues. We have some ideas but again its an area to think about. This is a think tank, any idea may have validity lets hear them. We have resources to do some cool stuff that can keep our beasts out front at every track in the nation!

Dabigsnake

I'll be at Spring Mountain Oct 2-3. You?

SBC_and_a_stick

I like all of that work to keep the Z cool. My point was just that it is incompatible with statements like these "I agree with Bish, not all cars have issues and those that do were most likely either not prepped correctly or have there own specific internal problem."

Folks will read this and think, oh, only a few Z06 have faults which lead to overheating. In truth, it's not a fault, it's a design limitation. There is a difference. Guys that had mishapped coolant tanks and water pumps desintegrate have faults, those are few. But every Z has the same cooling capacity with no faults and that is fixed, and inadequate. The fact that you have numerous cooling mods proves that the cooling is inadequate by design. Wouldn't you like to devote all that time modding for power or downforce? I know I would.

Dabigsnake

BTW, I totally agree with the blanket statement, and totally agree that all A8's will overheat at 80+ with a serious driver pushing it as it WAS designed to. It certain IS and WAS designed for max track capabilities in ALMOST every way. That is a FACT JACK, or Bish, etc. I know and have proven in over and over with documentation. I'm no professional driver, but I can drive agressively fast, but not for any 20-25 minutes without it overheating. I get 2-3 laps at around 2 minutes per lap, averageing 85-90 mph on Nola Motorsports 3.7 mile track. Just Sayin.

Dabigsnake

"I agree with Bish, not all cars have issues and those that do were most likely either not prepped correctly or have there own specific internal problem."

I guarantee I can take any freakin A* car you want and have it overheat within 3 laps at Nola Motorsports. forget all that pre talk and "specific internal problem" Damn it, you guys are off base totally, trying to make GM sound all fuzzy and warm. I love GM, but the FACT is, there is an inherent design limitation/flaw in this TRACK car. PERIOD!!! PERIOD !!!

GET it through your heads. Just because there are some (guys who really don't belong on a track, or with a real track car) out there that say "wow wee, my car did just fine....hmmmmmm, not sure how fast I was going, but Im betting I was flying...hmmmm, and when i looked at my temp thingy, it seemed just fine...hmmmmm!!!!
I'm glad you guys are happy putting around the track, (kind fast)

But this car has TRACK written all over it, for God's sake.

augerdogger

My track days have been both manually shifted and leaving it in drive. In drive it tends to stay at higher rpm while manually shifted I try to stay below 5500 rpm. Limp mode occurs in less than 2 laps in either mode, trans temp has NEVER been elevated. Oil temp runs 240-250F cruising the interstate at 75 mph and I went into limp driving up to a local ski area at 25-30 mph. I have never made 2 laps at the local track which is 1.7 miles, 1 min 20-30sec for a good driver, and I run 1 min 50+ sec. I have done all the recommended track prep and am waiting.

Minkster

Got some data to back up that statement specifically related to the Z07 RPO?

truth.b

This is a false statement. In my experience most track rats don't run stock cars i.e. street tires, stock seats, full interior, factory aero, etc.. IMHO, any upgrades beyond brake fluid and mild race pads with street tires, will stress any factory vehicle. The C6's are not different from the C5's, and the C7's are turning out to be the same. When capable drivers add mods such as tires, seats, harnesses, aero any corvette will need an upgraded cooling management system as well as better oil flow. I think that is just par for the course if you really want to go fast.

The truly astonishing part about the C7 Z06 is that it can turn approx the same times in full showroom stock trim without the additions of any of the mods I listed above. Which to me says when the cooling issues are fixed the C7 platform is probably going to be consistently several seconds faster that pretty much everything. With the exception of true race cars and the new viper ACR

JG853

What part about my statement is inaccurate? All cars suffer heat soak - Period. Super charged cars suffer even more than naturally aspirated cars as you should know. Of course a better radiator like the LG Motorsports Super Cool Radiator (And other brands) will help as it will help all cars. But show me the guys with C6 Z06's that have the cooling issues that the C7 Z06 does (Stock vs stock)? Where is this data?

That is what I was discussing as well as SBC and others. The C6 Z06 does not have a cooling problem - Period. It has had other issues that are well documented, but cooling it does not.