[DaveC113]

Originally Posted by GunMetalGrey

I just reread the other ice mode thread, just to be super clear Dave C113, when you swapped in a 2019 ABS module, it got rid of any ice mode problems for you? Or just reduced the severity of them? Or did you also have to change your driving style as well?
Have you been to more than two events since changing your EBCM as per your August 11th post from 2022? (I’d prefer a large sample size instead of small sample size just to make sure.)

It reduced the frequency and severity, but I also switched back to a staggered setup.

Severity went from severely limiting brake force for long enough to cause major issues to a momentary event that only extends braking by a relatively small amount, you might miss your apex by a bit but won't be going off course entirely.

I've done quite a few autox races and a couple track days since switching to the '19 EBCM.

[khcoaching]

Originally Posted by DaveC113

Agreed, it's not ABS anti-lock, it's the ABS system limiting overall brake force application to avoid a spin caused by braking while the vehicle is experiencing lateral g-forces. When it does this it's at the very beginning of brake application, nowhere near lockup.

If you're not seeing wheel speed differences ft/rear or side/side in the data as a trigger for brake force limiting, and the force limiting is more than momentary, then I'd think it's likely not ice mode, but exceeding the lateral-g / brake force limits that the car thinks is going to cause a spin. It feels like ice mode but what triggers it isn't the same.

Got it! You're correct on all wheel speed remain constant.

Ken

[GunMetalGrey]

Originally Posted by khcoaching

Another data dump!

As we all know, the faster you go, the less time you have. Meaning, if you are traveling the same distance in less time, you have to either - 1) Start your processes earlier 2) Use more force. For sure there is a ratio where one is faster than the other, which makes this sport so hard!

I looked a lot of data, focusing on where the issue happens and what my motor controls looked like. I also did this with all the different tires I have run, plus when Randy Pobst drove my car. (BTW, his first comment was how outstanding the brakes were)

The consensus is - Initial brake application where I apply the brakes in UNDER .4 of second can induce this. Brake applications OVER .4 it seems to not be an issue, regardless of the pressure. When applying them at .4 or under and we stay at say 1000-1200 psi or lower, no issue. When going over 1200, it seems to be more prevalent. I think the answer is to be precise with initial brake application when at pace.

Note - IME, .3-.4 is an acceptable amount of time for a brake build when hauling ass. Less than .3 is where we call it abrupt.

Here we go where I am looking at how long it takes to build brake pressure. (Times are close and I concentrated on the initial build until it stopped it's initial upward movement)

Thanks for this Ken! That is really good to have actual real data and proof that driving style and braking input seems to be the main factor, of course it’s impossible to tell exactly how much the other variables such as brake pads, and tires impacted or accentuated this, but it would seem obvious that as has been explained already, a more aggressive brake pad, especially if out of proportion compared to the grip level of the tire, would create more ice mode

A couple questions for everyone...

What if any role do you think that the slicks play in the recently reduced amount of icemode from your last two track days? Or did the data show you were just braking differentlly? My guess is that those slicks are more evenly and appropriately matched with the grip level of the brake pads you have on the car now.

Did you notice any correlation between ice mode and how fast you transitioned from gas to brakes?

Lastly, you don’t have any PDR video of your ice mode incidents do you?

[GunMetalGrey]

Originally Posted by Christian1LE

You actually will not necessarily lose laptime by braking earlier and softer. You can still maintain the same average speed in that distance vs braking hard and late. You would just suffer in race situations where someone is trying to pass you. I don't have any data to back this up in the real world but it works in simulators. (Comparing data vs real life drivers). The most important thing is always to carry as much speed as possible into the corner without overslowing.

I agree that you always want to carry as much speed as possible into and through a corner, but how long it take to drop to that speed is important too... Like drag racing trap/final speed vs the acceleration is takes to get there, they both matter

Having said that, it sounds like with Ken's data, if done right, applying full braking by .4 seconds should not really should impact lap time significantly, I think the hard part would be to not overdo the slowing of the brake application when changing braking style

[GunMetalGrey]

Originally Posted by DaveC113

It reduced the frequency and severity, but I also switched back to a staggered setup.

Severity went from severely limiting brake force for long enough to cause major issues to a momentary event that only extends braking by a relatively small amount, you might miss your apex by a bit but won't be going off course entirely.

I've done quite a few autox races and a couple track days since switching to the '19 EBCM.

Ok thank you for clarifying, that is very important for me to know!

One thing I should say is that I forgot that the fact that my main wiring harness that runs the entire length of the car was literally melting from being too close to the long tube headers and was causing a variety of other problems like; my steering locking momentarily mid corner, my gears shifting on their own despite being in manual mode, random horn honking on corners and finally traction control and stability control failed later as well... so some of the "ice mode" I was experiencing could have been from this as well (It cost $12,000 to replace the wiring harness after failed attempt to splice all of the wires back together again).

Fingers crossed that this was making ice mode worse than it should’ve been because going off the track three times in three half track days really scared me considering dirt banks and walls were next…

[GunMetalGrey]

I'm also going to try the Hawk DTC60's front and rear and see if that helps make a different compared to the Hawk DTC70's

[cdrptrks]

Originally Posted by GunMetalGrey

Did you notice any correlation between ice mode and how fast you transitioned from gas to brakes?

Lastly, you don’t have any PDR video of your ice mode incidents do you?

In my 2017 SS 1LE having a very short time between transitioning from full throttle to hard braking seemed to make ice mode more likely at MSR Houston Clockwise before the launch (bumpy braking zone), and before the first turn on Supercar 3R tires with stock brake pads (not recommended, also not a particularly bumpy braking zone). But that is based on subjective feel, not hard data like Ken provided. I'm using my right foot for throttle and brake; I'm not left foot braking.

I only have a few sessions on the 3Rs at this track but definitely felt I was having to hold back under braking more at this track than the several other (smoother) tracks where I have also driven on the 3Rs.

Here's my PDR video of Harris Hill before/after EBCM swap on stock Supercar 3 tires. I was purposely trying to stab the brakes hard right after full throttle for many laps here and at MSR Houston Clockwise but never got ice mode with the updated EBCM while I got it multiple times at both tracks by accident with the stock EBCM including a trip into the grass in the same spot at MSRH at 2 different events months apart.

https://youtube.com/watch?v=TLDWA4nfqX0

[GunMetalGrey]

Originally Posted by cdrptrks

In my 2017 SS 1LE having a very short time between transitioning from full throttle to hard braking seemed to make ice mode more likely at MSR Houston Clockwise before the launch (bumpy braking zone), and before the first turn on Supercar 3R tires with stock brake pads (not recommended, also not a particularly bumpy braking zone). But that is based on subjective feel, not hard data like Ken provided. I'm using my right foot for throttle and brake; I'm not left foot braking.

I only have a few sessions on the 3Rs at this track but definitely felt I was having to hold back under braking more at this track than the several other (smoother) tracks where I have also driven on the 3Rs.

Here's my PDR video of Harris Hill before/after EBCM swap on stock Supercar 3 tires. I was purposely trying to stab the brakes hard right after full throttle for many laps here and at MSR Houston Clockwise but never got ice mode with the updated EBCM while I got it multiple times at both tracks by accident with the stock EBCM including a trip into the grass in the same spot at MSRH at 2 different events months apart.

https://youtube.com/watch?v=TLDWA4nfqX0

Thanks that’s also really good to know! Giving me more confidence

I’ll watch that vid soon

[N Camarolina]

Originally Posted by cdrptrks

Here's my PDR video of Harris Hill before/after EBCM swap on stock Supercar 3 tires. I was purposely trying to stab the brakes hard right after full throttle for many laps here and at MSR Houston Clockwise but never got ice mode with the updated EBCM while I got it multiple times at both tracks by accident with the stock EBCM including a trip into the grass in the same spot at MSRH at 2 different events months apart.

https://youtube.com/watch?v=TLDWA4nfqX0

I watched the vid and can clearly see the benefit of the new EBCM. I also noted on both old and new EBCM playback vids, you seemed to have pressed the brake pedal as far as it could go (4 or 5 red bars), which I presume must have invoked ABS (not ICE mode, just normal ABS) and been less effective braking than just below the ABS threshold.

That said, while on track I have trouble feeling ABS activate through the brake pedal on my 1LE. It doesn't seem anything like the usual vibration feel of everyday cars.

Can you describe what YOU feel through the pedal when your ABS activates?

[cdrptrks]

Originally Posted by N Camarolina

That said, while on track I have trouble feeling ABS activate through the brake pedal on my 1LE. It doesn't seem anything like the usual vibration feel of everyday cars.

Can you describe what YOU feel through the pedal when your ABS activates?

Same here, I have trouble feeling ABS in this car. I can hear the front tires doing a chirp chirp chirp under hard braking when they're cold when ABS is preventing them from locking up but I can't hear that when they're hot. A buddy commented that he could hear my ABS engaging while watching me trackside at Cresson during the first session when temperatures were in the 30s and track grip was not good.

I did an autocross school shortly after I got the car and remember feeling ABS a bit through the pedal when the exercise was to purposely engage it by stomping the brake pedal but that was years ago.

How do you check for ABS engagement with the PDR .mp4 file on a computer?

[N Camarolina]

Originally Posted by cdrptrks

Same here, I have trouble feeling ABS in this car.

How do you check for ABS engagement with the PDR .mp4 file on a computer?

Use PI Toolbox software (free). This is not the same as Cosworth Toolbox (also really cool, but doesn't show all telemetry the car is collecting including ABS activation)

Once you learn how to use PI toolbox to access and plot your laps as graphs, there is a sensor channel you add to the plot for ABS. For each lap plotted, you can look at any point in time during a lap to see if ABS is off (Y axis value =0) or activated (Y axis value =1). Looking at brake zones (speed dramatically decreasing, brake pedal pressure increased), you'll be able to tell if ABS activated and how much pedal % it took to trip it. Also will show you whether you had any ABS during trail braking toward to the apex (that's usually where I'll see an infrequent ABS blip that I could not sense was happing in real time - I'm not activating ABS during straight line braking).

You can do the same thing looking for stabilitrack activation (it has a sensor channel for that), in the event you are running PTM Sport 1.

[Christian1LE]

So, no issues this weekend at VIR with hawk DTC 60s on the front and rear. Using 315/30/18 square all weekend, and I pushed the car as hard as I could, I almost felt bad. Went through the esses flat, now there is no going back to lifting anymore.

[khcoaching]

Originally Posted by Christian1LE

So, no issues this weekend at VIR with hawk DTC 60s on the front and rear. Using 315/30/18 square all weekend, and I pushed the car as hard as I could, I almost felt bad. Went through the esses flat, now there is no going back to lifting anymore.

Nice!

Remind me, you were on the 70s on the front before?

[Christian1LE]

Originally Posted by khcoaching

Nice!

Remind me, you were on the 70s on the front before?

I had 60 front and carbotech XP12 rear. Now it's 60's all around.