In-Car at Willow Springs + Off-track dirt action...Thanks Ice Mode...

M.Bonanni

So here's the short version of the story behind this video. It's nearly 8 months old and I never intended to do anything with it, but the other day I decided I wanted to start teaching myself the basics of video editing so I pulled this footage up and the end result is this video.

This is video from the last time I will ever track my 370Z...at least until I can get another daily driver and turn the Z into a dedicated track car. Why? This was the single most frustrating day I have ever had at a race track. After battling with the lovely ice mode issues most of us are plagued with, I went to this event with the primary goal of testing the last few ideas I had to combat the issue. None of them even remotely worked which left me with zero confidence in the brakes. Determined to salvage the day I just tried to push on and log seat time even though I was losing seconds a lap braking super early with less pedal pressure than I use during normal street driving. Late in the day I decided to start trying to carry a tad more speed and that's when the ABS bit me in the *** and tried to straighten the car out while the track was turning. The ABS and I had a small fight and the ABS ended up winning and the left side tires got in the dirt between turns 8 and 9 and there was no saving it from there. Fortunately it ended up being an uneventful off-track excursion as it could have been MUCH worse at this area of the track.

Although I wasn't happy with the car or the lap time, I still ended up getting 2nd in TT-S so I guess I can't be that bummed.

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GaleForce

Nice job. I like the fist shaking at the end. Did you try editing the video with the cockpit view in the lower right corner? I kept wanting to "look ahead" at the track but couldn't. I'm not even sure that would work.

What program did you use for the editing?

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M.Bonanni

No I was just happy enough to figure out how to do the PIP thing I didn't mess around with it haha. Using a free trial of Adobe Premiere Pro CS6.

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GaleForce

I really like it. You did a great job figuring it out. I also like the "info screens" or whatever they're called. I'll have to look into Adobe Premiere. Right now I use iMovie and don't have a clue what I'm doing with it. lol

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M.Bonanni

Thanks!

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DR_

Have you just turned off ABS? I think if you do you might find what is causing your tires to want to lockup in the first place. It might be a suspension or brake setup issue. Many don't have the issue so there has to be a fix.

EventHorizoN

Cool Video Buddy! I really enjoyed the in cockpit view~

Here is my video of me running 2:01.7 at Button~ Hope you like~

https://vimeo.com/58081295

M.Bonanni

I haven't personally tried disconnecting ABS as I have been told that because the car has electronic brake distribution when you disable ABS it defaults to 50/50 brake bias mechanically which would be way too much rear brake which means it would be super easy to lock up the rears and spin.

From talking with countless people, professional race teams, etc. I am subscribing to the theory that the ABS computer has parameters set for wheel speed, steering angle, g-forces, brake pressure, etc. If you exceed the parameters through a number of possible situations like too much brake pressure + too much steering angle then the ABS computer triggers ice mode as a safety measure to prevent a spin. I think the settings for the parameters are way too low for driving this car on the track. Plus I think modifying your car only makes it more likely to happen. Adding things like a limited slip differential will change the wheel speed in the rear compared to the stock VLSD. Adding things like suspension and sticky tires will mean you are capable of more lateral and braking gs. In my particular case in the video where I had the off, the mph is high, the car is turning so there is steering angle, and that combined with g-forces above what you would see on the street meant that I was probably already violating the computers parameters so as soon as I even breathed on the brakes the ABS tried to straighten the car out and because I was already at the edge of the track it was enough to put my left side tires in the dirt.

Trust me, I have been battling with the ABS ice mode situation for a long time. I've had the ABS system bled, made sure my fluid was filled all the way, tried multiple brake pad compounds and combinations, etc. As my car and my driving got faster the problem got worse which is why my 370Z is retired from the track until such time as I can make it a dedicated track car and go with an aftermarket dual master setup bypassing the ABS all together.

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ryan0

every car ever gets squirley there.. track falls away slightly.. usually windy and dusty..

plus most of us have a tendency to make the car squirley.. coming in with tons of speed.. real hard to see the edge of the track.. focusing on setting up for exit of 9..

i have yet to drive a car whos back end doesnt dance when braking late going into 9.

thats a lot of steering angle to be braking like that no?

braking needs to be done WAY earlier as you straighten out before turning in...


...in my opinion.. and what do i know.

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... needs more NOS.

ryan0

how does ABS try to 'straighten the car out'?

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... needs more NOS.

M.Bonanni

I wasn't going quick enough to do any serious braking. I just needed a tiny speed adjustment with a slight slight brush on the brakes but as soon as I touched the pedal ABS kicked in.

It engaged the left front brake for a quick second. Nose dove down, rear unloaded, car got loose left side tires went off the track.

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ryan0

Ummm wouldn't ABS provide LESS bite up front than no ABS at all?

ABS pulsates the brakes providing less stopping power and no lock up, no?

ANY braking there will lighten the rear end and cause it to step out. Thus the whole "brake in a straight line" theory.

And it only applied to the left caliper?

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M.Bonanni

It was more braking than I wanted. It was probably both fronts but the left front was loaded so I felt it much more on the left front. Bear in mind we are talking about super super super light pedal pressure here, not even close to threshold, I just needed to slow down a few mph. The amount of pressure applied by the ABS was more than I wanted and more than the car wanted obviously. I hope this doesn't come out sounding like a ****, this wasn't my first track day and certainly not my first time at this track. I am aware of the principles of braking.

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ryan0

trust me, i've seen plenty of guys who have plenty of track days screw up 9.. i've screwed up 9 in one way or another every time i've been there.

so you're saying that you barely touched the pedal and the car just applied tons of brake by itself? is that common?

most people complain about their car's mythical 'ice mode' as being "i broke normally and the abs kicked in thinking the wheels were locking up when they weren't".. thus the term 'ice mode'.. supposedly the car thinks the fronts are easily locking up (like you were on ice) and ABS kicks in, pulsing like crazy preventing you from stopping in a timely fashion... which in theory would help if you were on ice, but since you're not, it just extends your braking distance... ie. less actual braking.

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... needs more NOS.

martin82

Hey Ryan, I actually had this happen at buttonwillow, I had dead tires and dead pads about 3mm left on front pads, the abs or something would make one caliper brake up front!! Scary shhiet!! With full pads, rotors etc never happens!