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

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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