mcar00

Took my 2019 Z06/Z07 M7 to it's first track day at Sebring. Was watching water temps carefully but really wasn't an issue (well no limp mode anyway). Instead the trans temp bar got to the yellow block and then upper red block warning. Didn't see that one coming. Anyone seen this before? Car has not previously been tracked and only has 4,000 street miles so hard to believe the fluid has deteriorated. I'm thinking I'll change the fluid and look for any leaks I guess. Any recommendations for fluid brand/type? Thanks.
Mike

BrunoTheMellow

Wrap the exhaust with lava or titanium wrap from. Anywhere. 2" wide. Start from the xpipe (basically as far forward as you can reach without removing the tunnel cover plate) . End up above the trans as far as your arms can reach.
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Trust me. That will fix it. I run 100+ ambient temps on slicks. Don't even look at trans temps anymore.

LT4CMG

Just curious, 19 Z06, what's a normal range for oil and coolant temp city driving? Say an 85 degree day. Thanks

Lasco001

It really helps a lot
However, a second Oehl cooler for the gearbox is perfect

mcar00

That's great advice. Much appreciated. That's what I love about this forum.

Mike

mcar00

I'm probably not the right person to answer that. The car goes back and forth from the track to the gas station, and way more often than I would have anticipated BTW. First car I've ever tracked that can only make one 30 minute session on a tank of fuel. Doesn't empty it but not enough left for a second session.

From what I understand these cars have no overheating issues during city driving and will operate at normal passenger car temperatures.

LT4CMG

Thanks. No worries on overheating for my purposes, but I’m curious what “normal” oil/coolant temps are on the 19 Z

As for your fluid question, in my 13 1LE and my 16 Z51 (TR6060/6070), I swapped to Mobil1 synthetic AFT based on my conversation with a Tremec rep at a testing facility. Instantly got cooler temps and smoother shifts, especially on my 1LE I used to track. Of course, the wrap suggested my Bruno is the real solution, but as far as fluid, Mobil1 worked well for me. GM now recommends this for all A8s. Look into this one too.

mcar00

That will be first on the list. Thanks for the tip!
Mike

Pacembellum

Lowers the trans temps a lot. Wrapped my zr1 mufflers I’ll have data tomorrow night.

Dr.Ron

How much wrap does that take to do? 1 roll? 2?
Ron

BrunoTheMellow

I think 30-40 ft total

fatsport

I run Redline D4 ATF, also have a Borla X-pipe if that matters. My transmission temps at Sebring we’re typically about 10F lower than water temp, maxing out at 260F on a longer session. I’m pretty conservative with gear choice though, only use 2nd gear coming out of turn 7.
A friend who I run with wrapped his pipes as Bruno did. We’re both pretty new at this, typically running laps in the mid 2:20s.
What did you think of the car?

Dave

mcar00

I'm coming from stock C5 Z06's and a modified C6 Z06. This car is stock except for tires and brakes. I thought the car was very predictable, consistent and easy to drive. I'm about 4 seconds off the pace of my modified C6 Z06 but it's not really apples to apples. Definitely not up to speed yet so anything 4 seconds off the pace is going to be easy to drive. LOL My first time on a track in 7 years so that didn't help either. The biggest difference in the 2 cars I believe is this one is carrying around an extra 300 pounds or so. I did all 3 sessions in Track/Sport 1 which I thought was as intrusive as C6 competitive mode. I can feel it overslowing the car when I trail brake into a turn. I ran Hoosier A7's which kinda gave up in afternoon 90 degree heat. Probably should use R7's in the summer. Couldn't believe how much fuel the car used. Got ready for session 2 and never considered checking the fuel gauge since I started full. Big mistake! Cost me an extra $50 for track provided fuel. Really the biggest change I saw was, previously I would say there would be 90% street cars and 10% race cars at a Chin event. Fast forward 7 years and there may have been more crew members than there used to be street car drivers. There were many well prepared factory race cars there and haulers everywhere. Seems like maybe twice as many race cars as street cars now. I think that's pretty cool though just different.

Dave, I'm signed up for the next Chin Sebring event in 2 weeks. If you're there stop by and say hi.

Mike

fatsport

Glad you like the car. Fuel mileage is crazy, I get about 4 1/2 mpg. I think it’s cat over temp (COT) kicking in at high rpms, car runs very rich.
I cook my front brakes when I use Sport 1 at Sebring. It likes to correct for me a lot, lol.

I’m out for a while, got some stuff going on affected by the economy. Hopefully I’ll be back out there later this fall.

Have you been to The Firm in Starke, Fl? It’s a crappy venue, but a great little track to dial in your skills again. Open track days pretty much every weekend for $240 a day. I’ll probably go there first, can’t wait.

Cheers,

Dave

Black E

I was at Sebring yesterday, very hot day... also on a 19 M7
i do have the exhaust wrapped like Bruno mentioned and my max trans temps are ~240, also running mid 2:20’s on NT01’s

mcar00

That's good to know. I can tell you that based on your results and my experience from Sat. the wrap decreases trans temp by about 40-50 degrees which is huge. I'll get that wrap done before the June 13 event and report back. Do you usually attend the Sunday events as opposed to the Sat. events? I think their July and Aug events are Saturdays only. Hope to see you out there at another Chin event.

Mike

Black E

Yeah I like the Sunday better. Less crowded and by the end of the day you end up on track with 3-4 other cars for a hour lol.
I forgot to mention that I am running the Amsoil Signature ATF, has good luck with that on several cars.

July and August at Sebring sounds awful, that heat is just brutal.
And now that we can’t use all the garages because of covid....that back paddock seems like it’s 20* hotter then the garages!

BrunoTheMellow

It's hard to figure out the temperature increase because unlike oil and coolant It just doesn't cool back down between sessions because there is no fan on the cooler, if it had a fan and a manual switch you could cool it in the paddock or something. In the 100s it rises at about 70°F per 10 minutes. In the low 200s it's about 50°F and in the high 200s it's about 25°F per 10 minutes.

It was 90 out yesterday. I started the session with 200 trans temp. In 20 minutes it got to 285°F. Full tilt the whole time. This is not a 20 minute session, this is 20 minutes of 9/10ths. So like a 30 minute session.

In another session where trans started at a more normal 150°F, it rose to 235°F in 15 minutes. From experience it will be fine up to the end of a 30 minute session.

mcar00

So what you're saying is it's a cumulative heat problem that just gets worse as the day goes on because the trans never really cools down much? Would a 15 minute fuel trip in between sessions give you a lower starting trans temperature? Even with the heat wrap you still got up to 285 degrees?

fatsport

No garages, what? I couldn’t imagine doing a day at Sebring without the garage. I always bring a box fan too.