wmrexd

2015 Z06. What are the max. temp. we should expect while running the car on the street hard at appox. 5000 ft alt.>

Foosh

I don't have experience with this car at the altitude you cited, but at sea level, it's not unusual to see oil temps at 225º and above running hard on the street in hot temps, and coolant temps at 215º and above.

However, it's important to remember that the system is under pressure, and w/ the antifreeze mix, the coolant boiling point is well above 250º. Those are my sea level numbers, and at 5K ft., the boiling point will be lower.

owc6

My coolant temp is 220 year round, except when (like today) it's over 90 and I'm running the A/C, and I am running high RPMs. Then it will creep up to 230 or more if I keep the A/C on. I turn the A/C off, and it goes right back down to 220 no matter the RPMs.

I guess I shouldn't run around making so much noise, but it's so freaking fun! Yes, I'm a bad, bad girl.

Foosh

Interesting. I'm a bad, bad boy too, even when I'm not "speeding" because it's so much fun, that I can't help but keep the revs very high in my M7 in lower gears much of the time.

I've never seen quite 220º coolant temps even on days like today w/ the AC on full cold stun mode. On the highway mine runs 204-208º, and when horsing around on curvy roads, I 've seen as high as 218º, but usually 212-215º w/ AC.

My oil temps are frequently between 225-230º, but come down relatively quickly when highway cruising.

Obviously, like you, I'm not tracking a convertible, and mine is one of the last 14's built while yours is one of the earlier ones. The only reason I mention that is the frequent reports here of later MYs running much lower coolant temps often below 200º. Maybe they are just "granny" drivers.

EDIT: It just occurred to me . . . are you reading the hard gauge or the digital readout on the DIC in Tour mode? My hard gauge also reads 220 all the time too, even when the DIC is indicating 204.

owc6

Are you talking about the analog temps on the right or the digital temps when in tour display in performance?

On the '14s, those can be ten degrees different, with the digital temps reading lower.

Foosh

Yep, as usual thinking the same thing. I don't believe the analog gauge since it never moves, and always cite the digital figures.

owc6

From what I understand, the two are not gathering data from the same places in the '14 (two sensors in different places).

I'm also under the impression that on later MYs they are only one sensor.

If I am wrong, people please correct me (if you know for sure).

Foosh

Perhaps, but I keep hearing consistent reports of 190º coolant temps on 16s and beyond. You and I have never seen that even at 15ºF. I'm not concerned about it because in modern cars, cooler is not necessarily better.

Also BTW, the reason I believe the digital numbers, is that my digital temps always spike after I'm revving the hell out of it, and then settle back to 204º or so when I'm being good. The analog gauge never moves after going up to normal operating temp range.

owc6

Well, at 15 deg, I'm taking the blue one, because I don't have A/S tires like you do on the '14. But I'm not complaining, Bertha is darn fun to drive, too.

Sorry, OP, we got sidetracked, but I do think we sort of answered your concerns (and set them to rest, hopefully) about temps.

Elvira15

I live at 6700 ft, and rarely go over 210 deg. I drive pretty aggressively on some twisty mountain roads with no overheating problems at all.

Happy driving!

NSC5

I have a 2016 Z06 so it doesn't have a dedicated analog gauge but I usually have engine temperature displayed on a fake analog gauge in the DIC area. That gauge perfectly tracks with the digital readout on the tour mode digital display.

Under hard/high RPM acceleration the simulated gauge will spike pretty quickly followed shortly by an increase in oil temp on the pocket gauge. The normal operating temperature is 190-192. Yesterday it was 97 degrees and I accelerated a little harder than normal getting onto the interstate because there was a line of semis in both lanes fast approaching the on-ramp and I merged in ahead of them at well over 100. Fortunately there wasn't a state trooper nearby and that was faster than I normally merge but I have been using the Range module lately and was enjoying the 8L90 in full auto mode which is a lot of fun. The engine temp briefly hit 206 before dropping back to 195 after a couple of interstate miles cruising at 80 and the oil temp stayed right at 200 for about 10 miles before starting to drop.

The LT4 (and presumably LT1) do seem to heat up more at higher RPM than past engines with which I am familiar. Even under engine braking in the mountains when I was forced to downshift low enough to keep the engine near 5000 RPM for about a mile the engine coolant temperature came up well above its normal cruising temp instead of falling like most engines. It makes me wonder if the water pump in these engines tends to cavitate at high RPM.

Foosh

Yes, that confirms what my impression was of later models. The 2014 LT1s all seem to run at 204º-208º in normal highway cruising/low rpms, and between 212º-220º when keeping the revs up.

50th year

My car runs a good 20 degrees hotter if iam using the paddles.

NSC5

Time to short shift

GM could have saved themselves some grief if track mode on the Z06 caused the A8 to short shift; it wouldn't have been honest but it would have helped to cover up the lack of sufficient engine cooling capacity AND they could have blamed the owner if he/she manually shifted on the track.