briann510

Have always driven my Z06 very hard on the street, yet today was the very first time I had to brake really hard on a freeway transition ramp in hot weather (with Nitto track tires on car) where ABS came on. Not even on the track has it ever applied with hard braking.

I was hard into it top of 3rd and halfway through it the BMW in front of me decided he wasn't going to be able to handle it at that speed and he braked hard.

I had plenty of time to slow down, but hit brakes hard anyway to be safe behind the guy in front of me and I guess my car didn't like braking that hard in the middle of a sweeping right hand turn. The car shook and the ABS active display flashed on the DIC and I let up slightly and all was fine. It was 105 out but brakes cool as I had been on the freeway without braking for a while. Just caught me off guard that it happened so fast.

Bill Dearborn

It sounds like it worked just exactly as designed. It only takes one wheel on the verge of locking up to activate ABS at that wheel.

Bill

BlackZ06

105 degrees om a Cali freeway ramp ..... you're lucky given the following ...

1) At that air temperature the asphalt was probably at 140 degrees, or more. Unless your tires are "high performance summer tires" (like the Goodyear F1 Supercar tires) they willl lose grip at that kind of temperature.

2) You may have experienced "snap braking" .... you hit the brake pedal fast enough that before weight could transfer to the front tires (increasing grip) you generated enough brake pressure to "lock" the front tires ... which would cause the ABS to step in

3) A BMW has very good brakes .... if he was close to maximum braking power in his car ... so were you. We can easily out-brake most cars, but a BMW is not one of them ....

4) Your Vette did exactly what it was designed to do .... it told you that you has pushed the envelope beyond what a normal car can do, your braking requirements were beyomd what your car is "normally" capable of doing.

Thank God for ABS ..... I know it kept me from stuffing the nose of my Corvette into the rear of a BMW at Laguna Seca one time .... it is a GREAT safety system.

briann510

I have Nitto road race tires on the car when it happened and they grip like glue in hot weather like this street driving. You guys are right as I was hard in the sweeping turn and I think it was the front right that was on verge of locking briefly then left then ABS came on. Was actually kind of interesting as it happened and how it happened. Just caught me off guard I guess. I generally take this transition hard well into 4th, but was obvious the Beemer driver was safety conscious instead of trying to impress me and lose it. I am going to remove all the wheels tomorrow and flush out the brake fluid and check everything just to be safe.

I guess even after 35+ years of driving SCCA, GT-1 and IMSA things still surprise me.

DeeGee

The guys who post that they switch off AH as the norm would do well to read this

Glad you're not posting an "I wrecked my Vette thread"

AH saved me once.

trussme

(I believe) "switching off" Active Handling, removes A/H & Traction Control...but not ABS.

briann510

I believe you are right. I was in comp mode as I never drive with traction control on.

Rogue Leader

You are correct, the only way to shut off ABS is to unplug the whole AH/TC computer attached to the brake valves (the computer that craps out all the time).

trussme

YES... ..."Comp" mode leaves both A/H and ABS ON.

DeeGee

I guess everyone missed my point. I understand which is automatic and which can be inhibited by the AH switch.

ABS is designed to protect us although theres no control, over that function. AH is also designed to assist handling as is Traction control.

When you disregard the protection built into the car you do it at your peril. Glad the ABS helped out. If you turn off the other protection deliberately, running the car at the edge may catch yuo out one of these days.

A wise man taught me someting very early on in my flying career. There are old pilots and bold pilots; there are no old, bold pilots.

DeeGee

You may want to start. You're a bit closer to the limit than you thought

A friend of mine killed himself in a Phantom in the 80s. he was just taking it that bit closer to the hill that killed him. He was really talented pilot

JMHO

briann510

Ive been racing SCCA GT-1 GT-2 IMSA and Formula cars for 35 years and have never had the need for ABS, AH or TC. I do not need a computer trying to drive a car for me or telling me I've reached limits. I do fully understand most people needing it for when that unforseen event happens and it will indeed help you out of it but I prefer to get out of situations myself.

In my case yesterday with ABS coming on it almost caused me to lose control of the car. I had already come to the mph I wanted to slow down to right as the ABS came on and I would have been just fine had it not. I have almost wreck my Z 3-4 times from either AH, TC or ABS coming on when I didn't want it to or actually need it.

Anyway.....live and learn

DeeGee

Good to see you have that experience and you're way better placed than most. I do take your point.

But ....... Another old fighter pilot adage

Its the the one you don't see that kills you

Glad it worked out.

briann510

Couldn't agree more. I believe AH/TC and ABS are best suited for rain/snow driving, BUT will indeed help save anyone from the unforseen emergency situation.

Bill Dearborn

Actually they are great if you use them. They will do nothing to fight you. With ABS I stop quicker and straighter, with AH I can make the car do things that normally couldn't be done. AH applies the brake to just one wheel to get the car to rotate in the direction you want to go. Can't do that on a car without AH.

Go out to some parking lot and find out how to use them Vs complain about them. They are more than safety nets when used purposely.

Bill

briann510

Just for comparison I can run consistently better lap times with it all turned off. Traction control will kill me on lap times, 1/4 mile racing and running in the twisty back roads. AH will throw the car into situations I'm not anticipating also. I've never had the ABS come on with track road racing in the last 4 years either so that function doesn't bother me at all. I'm not complaining about it, just commenting there is a time and place to have it all on and times not to use it, none of which apply to me and some other very experienced track drivers out there. When I was teaching my wife how to really drive really aggressive on the track we turned it all off also. With it turned on it she couldn't hardly drive the car and was turning horrible times.

Ok, I'm moving on as my driving style and turning it all off doesn't apply to most drivers out there.

You've been a great audience....drive safe!