Hard brake pedal after slalom in track-race mode - help!
06-03-2018, 05:53 PM
#22
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Bill
06-04-2018, 05:15 AM
#23
Le Mans Master
even if you do this and recognize it quickly, that's about 200ft of braking zone.200 ft is the difference between an easy turn and a wall for me in many circumstances.
Last edited by village idiot; 06-04-2018 at 05:16 AM.
06-04-2018, 03:44 PM
#24
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Later on the guy riding with me asked why I didn't hit the brakes until we were almost out of track. He didn't realize I had hit them quite ways back.
Bill
06-04-2018, 06:28 PM
#25
Le Mans Master
Yeah it always happens to me at the same exact turn.- because it's bumpy going in.
06-04-2018, 09:27 PM
#26
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St. Jude Donor '13
Does this happen to all models and years of C7, or just the GS/Z06, or ???
Anyone experience it on the street? The possibility of jumping on the brakes while on bumpy pavement doesn't seem unrealistic.
Anyone experience it on the street? The possibility of jumping on the brakes while on bumpy pavement doesn't seem unrealistic.
06-05-2018, 01:10 AM
#27
Le Mans Master
it's more pronounced on the track because you get to lock up so "easily." We have much more aggressive brake pads and I've noticed it only happens when something unloaded gets brake pressure. I.e.: when you're on the gas, loaded the front and unloaded rear. Or trail braking hard into a turn and hit curbing with outside wheel.
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serendib (06-05-2018)
06-05-2018, 04:47 PM
#28
My 2017 ZO6/ZO7 only "finds" ICE MODE when I run TIRES that are approximately the same OUTSIDE diameter front and rear. i.e. 305/30/19 RE71R front and rear.
Doing 0-100% braking on dry concrete and asphalt in a straight line has never invoked ice mode with the following tires:
A. PSC2 ZP 285/30/19 front (25.8" diam) front, PSC2 ZP 335/25/20 rear (26.6 diam)
B. PS 4S 295/30/19 front (26" diam), PSS 345/3019 rear (27.2" diam)
Once at 100% jam really hard and ABS will intervene 100% of the time with the above tires.
I have repeated these tests with Sport 1, Sport 2, and Track as well as everything off and the results are the same.
Doing 0-100% braking on dry concrete and asphalt in a straight line has never invoked ice mode with the following tires:
A. PSC2 ZP 285/30/19 front (25.8" diam) front, PSC2 ZP 335/25/20 rear (26.6 diam)
B. PS 4S 295/30/19 front (26" diam), PSS 345/3019 rear (27.2" diam)
Once at 100% jam really hard and ABS will intervene 100% of the time with the above tires.
I have repeated these tests with Sport 1, Sport 2, and Track as well as everything off and the results are the same.
Last edited by serendib; 06-05-2018 at 05:18 PM.
06-05-2018, 06:33 PM
#29
I have not had ice mode happen in braking on bumpy streets and now have 8,500 miles on mine.
Last edited by serendib; 06-05-2018 at 06:33 PM.
06-07-2018, 02:55 PM
#30
Intermediate
Thread Starter
This new realization of the capabilities of my brakes makes me want to refocus what car I put on a road course. I own a '71 Datsun 510 caged car that will now be getting my full attention. The Z06 will be relegated to being a pretty street car. So sad that I spent that much money on a car I no longer trust to stop me in time in a competition environment. Maybe GM will fix the issue and I can trust my car again.
06-07-2018, 03:38 PM
#31
Le Mans Master
This new realization of the capabilities of my brakes makes me want to refocus what car I put on a road course. I own a '71 Datsun 510 caged car that will now be getting my full attention. The Z06 will be relegated to being a pretty street car. So sad that I spent that much money on a car I no longer trust to stop me in time in a competition environment. Maybe GM will fix the issue and I can trust my car again.
06-17-2018, 08:23 PM
#32
Le Mans Master
I submitted this for ask Tadge. It's getting voted on so if you want to know why the heck this exists in PTM, go vote for it!
https://www.corvetteforum.com/forums...6-24-18-a.html
https://www.corvetteforum.com/forums...6-24-18-a.html
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06-20-2018, 11:33 AM
#33
Instructor
I voted for the Ice mode question. My car has never smelled the same since I **** my pants going into turn 10 at Hallett. The pedal felt like I was pushing on a brick and the car wasn't stopping. Truly terrifying, but it has only happened once to me. I am very quick off the gas and onto the brake and I usually brake very hard. I still don't know why it chose that one time to go into the I'm Gonna Die mode.
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06-20-2018, 11:55 AM
#34
Voted for it and this question does have the highest number for obvious reasons. It is unacceptable for these cars to invoke a hard pedal and reduce braking while eliminating ABS in any conditions. I have competed for 8 years in a Honda Civic Si, Chevy Cobalt SSTC, BMW E46 track car, BMW E92 M3, Audi TTQ and have never experienced an unexpected brake feedback in any of these cars. Never will forget my shock when my 2017 Z06/Z07 went into ice mode. I have also driven a gen 5 Camaro SS that goes into ice mode. I feel sure that GM can correct this issue with firmware reprogramming since most (if not all) other manufacturers don't have this issue.
Last edited by serendib; 06-20-2018 at 02:06 PM.
06-20-2018, 12:36 PM
#35
Racer
I voted it up 
06-20-2018, 01:14 PM
#36
Le Mans Master
Voted for it and this question does have the highest number for obvious reasons. It is unacceptable for these cars to invoke a hard pedal and reduce braking while eliminating ABS in any conditions. I have competed for 8 years in a Honda Civic Si, Chevy Cobalt SSTC, BMW E46 track car, BMW E92 M3, Audi TTQ and have never experienced an unexpected brake feedback in any of these cars. Never will forget my shock when my 2017 Z06/Z07 went into ice mode. I have also driven a gen 5 Camaro SS that goes into ice mode. I feel sure that GM can correct this issue with firmware reprogramming since most 9if not all) other manufacturers don't have this issue.
I will say it probably has a purpose- in weather mode in case you hit ice, I guess. Makes sense on, I don't know, a Tahoe- not a Corvette in PTM Race.
With that said, I wish there was a way to amend my question to ask if it can be fixed or what computer controls it :lol;
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06-20-2018, 01:43 PM
#37
Intermediate
Thread Starter
Voted.
And just for more info... I did an Autocross this weekend and experienced it again. We had a pretty high speed course with a short braking zone after the finish. I crossed the finish like at around 90 mph and 7 out of 8 runs, everything was great. But 1 run I had the hard pedal and very limited brakes. I swear my butt lifted off the seat from standing on the brake! I was able to stop within a few feet of blowing through the cones at the end of the stopping area, but it still sucked. Unfortunately, I don't know why it decided to do it on this one run. There were no bumps to speak of and it was pretty straight for a bit before the transition from gas to brake.
I hope this get's answered AND FIXED! I feel like I threw money away because I bought this car for driving on road courses.
And just for more info... I did an Autocross this weekend and experienced it again. We had a pretty high speed course with a short braking zone after the finish. I crossed the finish like at around 90 mph and 7 out of 8 runs, everything was great. But 1 run I had the hard pedal and very limited brakes. I swear my butt lifted off the seat from standing on the brake! I was able to stop within a few feet of blowing through the cones at the end of the stopping area, but it still sucked. Unfortunately, I don't know why it decided to do it on this one run. There were no bumps to speak of and it was pretty straight for a bit before the transition from gas to brake.
I hope this get's answered AND FIXED! I feel like I threw money away because I bought this car for driving on road courses.
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06-20-2018, 01:59 PM
#38
I’ve found I have to use a different brake technique. Instead of typical all on I ease to the level of brake I want very quickly. Never had a brake issue since. And I seem to out brake just about everyone. I use DTC70/60 combo with wonderful success.
06-20-2018, 02:00 PM
#39
Intermediate
Thread Starter
If I ever put my car on a road course, that's how I would definitely do it. But wouldn't it be nice if I didn't have to?
06-20-2018, 02:16 PM
#40
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St. Jude Donor '13
I must have missed something-
does the "ice mode" problem occur only when in Track-PTM?
Although I enjoy autocross and track weekends, I use them as "training" for high performance street driving. Since I normally don't use Track or PTM on the street, I normally don't use them on the track. Yes, my times suffer for it.
That's not to take away from the annoyance and danger to people who do run Track-PTM, regardless of the circumstances.
BTW, what experience does Spring Mountain have with this?
does the "ice mode" problem occur only when in Track-PTM?
Although I enjoy autocross and track weekends, I use them as "training" for high performance street driving. Since I normally don't use Track or PTM on the street, I normally don't use them on the track. Yes, my times suffer for it.
That's not to take away from the annoyance and danger to people who do run Track-PTM, regardless of the circumstances.
BTW, what experience does Spring Mountain have with this?
Last edited by Gearhead Jim; 06-20-2018 at 02:17 PM.