Along4theRide

Approximately 17-19 minutes into about a 25 minute session (3rd session of day, 1 hour in-between). Outside temps in low 70s.

kevincol

Wonderful. I'm taking my '16 Z51 M7 tracking on 8/11. I hope I don't face the same issues as you are. When I was at Spring Mountain I never had an issue with the same car, but it was only in the 50's and our lapping sessions were pretty dang short.

X25

Guys, you can just do what I did:
https://www.corvetteforum.com/forums...k-driving.html

When/if they come up with a solution for prior years, we can then get it. In the meantime, no one should deal with this mess.

I've made two track days since, and the last one was an open track day at 95-98 degrees F. So far, no issues with the actuators 'removed' : )

Regarding the answer, I am glad that the actuators are removed for the 17+ models, but it is still shocking that there is still no permanent solution. At the very least, GM should definitely let us stop by dealers and get it disabled. As far as I know, actuators stay open when disabled. They would just stay open, and even if the actual actuator malfunctions, since it is disabled, we'd not need to care.

djnice

Good call, I thought that might be a solution. We do something like that as a cheap quick solution on race bikes if there isn't a tuner around. You might even be able to remove the actuator so it can cycle while the valve remains open.

What happens when the car goes in eco mode without the valve closed? It seems there are noise and vibration issues. Is that true? Or maybe its only an issue on the auto...for some unknown reason that no one has explained yet.

SBC_and_a_stick

This is the solution. If some of you burned them in 70* ambient I wouldn't track again until this mod.

I'm surprised there weren't many driving the C7 hard enough to melt these every time. Claude must be one of the few driving the Stingray hard.

Jay_Davis

As sad as it may be, I think my A8 is protecting the actuators. It overheats before the actuators fail.

vettetwo

Check out this TechLink about track engine temperatures including a few comments about the A8 and M7:
http://sandyblogs.com/techlink/?p=4998

X25

Yeah, we've read all that before, including at Ask Tadge section.

Chets LS3

I have always used the cool down lap. To the point the car is in 6th gear and basically very little throttle and braking to allow the car to cool. Over been fortunate I suppose. Im also running the car on slicks along with some other things.

DLC7

Are you implying that some other drivers don't do cool down laps

For those that don't, try this next time for as a simple example. Next time you are done with a session, get out and get your ungloved hand as close to the rotors as possible. Toasty.

Than the next time do a full on cool down lap, and drive at least 5 mins at slow speed. Than get out and recheck. Not so toasty.
Notice how much less heat is present.

At WSIR this would mean driving to SOW, or even leaving the track and driving in the desert for 5 mins if too much traffic track side.

As to AFM, not quite sure.....but as a general precaution.....maybe it's b/c my track is in the desert......so maybe this is a common practice that gets copied locally.

In other parts of the country, do drivers do a cool down every time.? I would guess yes?

Laser pyrometry is also a more reliable way to check this.....than an ungloved hand.

truth.b

I made my statement not as an attack on the OP or any drivers. I have seen with my own eyes many guys coming straight off the track and just going to their parking spot in the paddock.

I agree on some tracks there isn't alot of room or time to do a full cool down lap. But even in the desert it should help because the temperature delta between brakes / exhaust / oil / trans fluid should be quite high. On the GS I tend to use at least 3rd because I want the engine well above idle but below the mid-range powerband, roughly just under 2500 RPMs. Through my testing this results in the quickest cooling on my car. Although it seems that it wouldn't help much for the drivers that are having failures during their sessions.

jvp

I appreciate the acknowledgement. And believe me, Tadge takes this as seriously as everyone here does. While he doesn't have the time to respond (through me) to everything, he still wants folks to know that he and the rest of Team Corvette care.

That may be because he doesn't have one yet, and therefore can't nor won't commit to anything. My sources tell me that Corvette did do some research due to this question, specifically on failure rates of the AFM exhaust modules. They've replaced fewer than 1% of them throughout the entire C7 run so far. That's why it hasn't really shown up on their RADAR until now. They acknowledge both that 1% is an insignificant percentage BUT that it still matters to the person that the failure happens to. So they'll keep looking into solutions.

Also, to address your first response a little more clearly: bear in mind that when Tadge writes his answers, he realizes that they'll be read by more than just the person who asked it. Therefore he attempts to address the general population with the answers. For instance, his mention of modifications to the car weren't to point a finger at you. Rather to let folks know what could be the cause and to make sure other readers also understand that.

I'm pretty sure this isn't "cased closed" from GM's perspective. While it may be frustrating to those that are affected, I'd say patience is a good virtue to have for the time being.

kenrobb

I had heard that the noise and vibration is a problem in the auto trans cars when 4 cylinder mode activates. That appears to be the reason i
they remain on the 2017 auto trans car.

BaylorCorvette

2016 C7 Z51 manual transmission, no mods and last time I was at the track I ended up melting the AFM actuators. I always run a cool down lap at half speed. I've decided to not run the car on the track in the summer months and stick to autocross only until it cools down. Very disappointing that they have a solution but it isn't backwards compatible. Fingers crossed that they come out with a solution for the 2014-2016 C7s.

daleong

Along4theRide

BaylorCorvette - You did nothing wrong. I always do cool down laps also, my failure occurred on the track, you can't very well be in the middle of a session, and stop to do a cool down lap. This *IS* a design issue with the car. As has been stated, it's so much of an issue, they changed the design of the car in 2017. The only thing left to do is form a prayer circle and hope that they don't forget the existing customers who already purchased these cars and are now left with the issue. Hang in there.

descartesfool

Might need to add some chanting to that!

IN54NITY

Kumbaya, Chevy engineers, kumbaya.

djnice

Since all GM did on the 2017 M7 is remove the valves it seems like they could just sell current owners a $200 track performance improvement upgrade that removes the valves and retunes the ecu.

daleong

One would think it would be that simple..