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Old 06-17-2020, 06:25 PM   #141
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Quote:
Originally Posted by lemming View Post
If the car has MRC, does that mean 1LE?


https://www.cars.com/vehicledetail/d...4097/overview/

The listing doesn’t say “1LE”
That is a very nice color for Camaro's
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Old 06-17-2020, 11:19 PM   #142
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Quote:
Originally Posted by lemming View Post
If the car has MRC, does that mean 1LE?


https://www.cars.com/vehicledetail/d...4097/overview/

The listing doesn’t say “1LE”
It’s a 1LE. It’s at a Jag dealer. It’s kind of remarkable how many non-GM dealers have listed 1LEs not knowing what they are and priced them as hough they are not. This one is priced kinda high, especially for already having two previous owners.

Even priced right, it’s not the car for me. Needs to be 2019 or newer. The 17s and 18s had an ABS calibration that isn’t very good for autocross. The brakes go into ice mode pretty easily and regularly in autocross use. Totally fine for regular street driving, track use and everything else. Just not good for autocross because of the weird shit we makes cars do. In autocross, there’s a lot of full throttle followed with immediate heavy braking while the chassis is unsettled. In the real world, this condition never happens except in limited traction circumstances where ice mode would be An appropriate response. They made a huge change for 2019 that all but eliminates the issue.
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Old 06-18-2020, 06:43 AM   #143
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I had ice mode trigger on me on an off-ramp in my 06 Cayman 987S. Still remember the exact off-ramp in Westchester, that I took somewhat aggressively, had no cars in front of me and what I thought lots of room. And then I noticed the red light I was heading towards at highway speeds. I did stop but the bumpy section threw my brakes for a loop on perfect, dry conditions. Pretty sure I posted on it.

While the "numbers" weren't bad on 987 brakes, they weren't up to par with 997's. The 981 has much better braking feel through different master cylinder - perhaps the programming changed too... I could hope. I haven't had the chance to enter 'ice mode' on my boxster, and happy for it.
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Old 06-18-2020, 08:21 AM   #144
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You guys just mean full ABS activation? Or is emergency "ice mode" an actual thing now, signifying more than just that?
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Old 06-18-2020, 09:47 AM   #145
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Originally Posted by Plaz View Post
You guys just mean full ABS activation? Or is emergency "ice mode" an actual thing now, signifying more than just that?
Ice mode has been a thing for a long time. It's where ABS radically limits the brake power even available in order to not lock up the brakes on ice.

IMO, it's misguided in a performance car.
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Old 06-18-2020, 10:12 AM   #146
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Originally Posted by Nick M3 View Post
Ice mode has been a thing for a long time. It's where ABS radically limits the brake power even available in order to not lock up the brakes on ice.

IMO, it's misguided in a performance car.


Interesting. Yeah I could see how that could go horribly wrong. Seems like something that the driver should deliberately have to activate unless they have a fool proof way of detecting that you’re on ice


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Old 06-18-2020, 10:37 AM   #147
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Interesting. Yeah I could see how that could go horribly wrong. Seems like something that the driver should deliberately have to activate unless they have a fool proof way of detecting that you’re on ice


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I don't understand why it's not linked to temperature readings. Over 40 degrees, it shouldn't activate.

That said, it's not really an issue in normal street driving. It's something that people run into when they are pushing the limits, which is why it doesn't really come up that much.
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Old 06-18-2020, 12:36 PM   #148
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In a normal ABS engagement on dry pavement, the brake pedal chatters as you push the pedal and the pedal pushes back with variable resistance as each wheel goes through a lock-release cycle. The vehicle slows throughout the ABS engagement as a result of the brake application.

The "ice mode" behavior I'm referring to is a fully stiff brake pedal without chatter while the vehicle does not lose any velocity from brake application because the ABS system is preventing the brake pads from being applied to the rotors. The reason it's called "ice mode" is because it's the behavior that occurs when you try to apply the brakes while on a sheet of ice.

In an autocross situation, we often have cars behaving outside normal behaviors. We'll often be at full throttle with a significant and rapidly transitioning lateral load followed in an instant by full brakes and a sharp steering input in the opposite direction of the lateral load transfer.

In normal street driving—even track driving—that situation strongly correlates to something bad happening. What the ABS calibration sees is something it interprets kind of like a driver over-correcting a fishtailing situation AND simultaneously jumping on the brakes which is highly likely to lead to a total loss of control and very worse things happening. In response, the ABS prevents brake application so the driver doesn't lose steering input.

When it happens, you basically have three choices. You can stand on the brake and wait it out for a predetermined amount of time (specific to the ABS calibration, but typically 1-2 full seconds) for the pedal to return to normal. Or you can lift off the brakes and immediately get back on them. The time it takes to release and reapply the brakes, the out-of-envelope conditions that caused the event will have dissipated to the point they're back within the envelope for normal braking operation. The third choice is to lift and just chuck it even harder into the turn you tried braking for. That last choice is often the least damaging to your course time, but it's never as good as it would have been without getting into the event.

When you walk an autocross course before driving it, with a little experience, you can see where it's going to happen.

So, while the conditions triggering the behavior are different, the resulting behavior is the same. Because autocrossers are simple people and we're describing the behavior rather than the conditions that triggered the behavior, we call both of those "ice mode." Except our GM engineer friends. They flip their shit when call the second situation "ice mode" because it's not. Even though it is. But anyway...

Like Nick said, it's not a new thing. The ice mode in icy conditions has existed in ABS (or similar) equipped cars since the 70s. The self-induced ice mode that I'm complaining about...I don't know how far back it dates. The oldest cars I'm aware of where it's an issue in autocross are both MY2002 cars (350Z and Corvette Z06).

In the past few years, it's been noted to be present on larger numbers of cars, but even where it's present, it can range from "yeah, it happens, but it's nothing to be concerned about," to "Fuck this! I know it's only been one event, but I'm selling the car."

Tying this back to the 6G Camaro... The regular 2016-2018 SS Camaros are hurt pretty badly by the self-induced ice mode. I know more than a couple people that reluctantly sold theirs because of it. Non-1LE SS Camaros with MRC shocks may be very slightly less prone to it, but no non-GM employees/suppliers are sure. 2017/18 (there was no 16 model) SS 1LEs have a different ABS calibration that is less prone, but it's still an issue.

For 2019, all 6G Camaros got new ABS calibrations that "fix" it. A few of the people I know who sold pre-fix SS Camaros now have 2019/20 SS Camaros and are very happy with they now have.

For reference, my 2017 turbo Camaro suffers from it, too, but it's not highly debilitating like the SS cars. I would have an ice mode experience once every few events, usually in connection with a fuck up. My co-driver would have at least one experience with it at almost every event.
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Old 06-18-2020, 03:07 PM   #149
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Quote:
Originally Posted by clyde View Post
In a normal ABS engagement on dry pavement, the brake pedal chatters as you push the pedal and the pedal pushes back with variable resistance as each wheel goes through a lock-release cycle. The vehicle slows throughout the ABS engagement as a result of the brake application.

The "ice mode" behavior I'm referring to is a fully stiff brake pedal without chatter while the vehicle does not lose any velocity from brake application because the ABS system is preventing the brake pads from being applied to the rotors. The reason it's called "ice mode" is because it's the behavior that occurs when you try to apply the brakes while on a sheet of ice.

In an autocross situation, we often have cars behaving outside normal behaviors. We'll often be at full throttle with a significant and rapidly transitioning lateral load followed in an instant by full brakes and a sharp steering input in the opposite direction of the lateral load transfer.

In normal street driving—even track driving—that situation strongly correlates to something bad happening. What the ABS calibration sees is something it interprets kind of like a driver over-correcting a fishtailing situation AND simultaneously jumping on the brakes which is highly likely to lead to a total loss of control and very worse things happening. In response, the ABS prevents brake application so the driver doesn't lose steering input.

When it happens, you basically have three choices. You can stand on the brake and wait it out for a predetermined amount of time (specific to the ABS calibration, but typically 1-2 full seconds) for the pedal to return to normal. Or you can lift off the brakes and immediately get back on them. The time it takes to release and reapply the brakes, the out-of-envelope conditions that caused the event will have dissipated to the point they're back within the envelope for normal braking operation. The third choice is to lift and just chuck it even harder into the turn you tried braking for. That last choice is often the least damaging to your course time, but it's never as good as it would have been without getting into the event.

When you walk an autocross course before driving it, with a little experience, you can see where it's going to happen.

So, while the conditions triggering the behavior are different, the resulting behavior is the same. Because autocrossers are simple people and we're describing the behavior rather than the conditions that triggered the behavior, we call both of those "ice mode." Except our GM engineer friends. They flip their shit when call the second situation "ice mode" because it's not. Even though it is. But anyway...

Like Nick said, it's not a new thing. The ice mode in icy conditions has existed in ABS (or similar) equipped cars since the 70s. The self-induced ice mode that I'm complaining about...I don't know how far back it dates. The oldest cars I'm aware of where it's an issue in autocross are both MY2002 cars (350Z and Corvette Z06).

In the past few years, it's been noted to be present on larger numbers of cars, but even where it's present, it can range from "yeah, it happens, but it's nothing to be concerned about," to "Fuck this! I know it's only been one event, but I'm selling the car."

Tying this back to the 6G Camaro... The regular 2016-2018 SS Camaros are hurt pretty badly by the self-induced ice mode. I know more than a couple people that reluctantly sold theirs because of it. Non-1LE SS Camaros with MRC shocks may be very slightly less prone to it, but no non-GM employees/suppliers are sure. 2017/18 (there was no 16 model) SS 1LEs have a different ABS calibration that is less prone, but it's still an issue.

For 2019, all 6G Camaros got new ABS calibrations that "fix" it. A few of the people I know who sold pre-fix SS Camaros now have 2019/20 SS Camaros and are very happy with they now have.

For reference, my 2017 turbo Camaro suffers from it, too, but it's not highly debilitating like the SS cars. I would have an ice mode experience once every few events, usually in connection with a fuck up. My co-driver would have at least one experience with it at almost every event.
Wow that reply took a lot of work. Thanks!

I suspect I'd lean heavily toward the "fuck this I need a new car after one event" camp. It sounds equal parts horrifying and infuriating, to any degree.
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Old 06-18-2020, 03:29 PM   #150
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Quote:
Originally Posted by Plaz View Post
Wow that reply took a lot of work. Thanks!
I left out a part at the end.

Quote:
I suspect I'd lean heavily toward the "fuck this I need a new car after one event" camp. It sounds equal parts horrifying and infuriating, to any degree.
Driving style has an impact, too. The more abrupt you are with inputs, the more likely it will be an issue in a given car for that driver. The smoother the driver is with inputs, the less likely.

I don't think I'd have a problem with it in a pre-fix 1LE, but when there's a fixed car available that's otherwise identical in terms of autocross and has a couple minor convenience improvements, I know what I'm doing.
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