Stability control is not fully defeatable?

[Sleepless]

Originally Posted by TrqlessWonder

Threads like this are why I don't come here looking for input on setup anymore.

Nice contribution then...

Seriously, like pretty much an thread of conversation with many people, you have to simply learn to filter out the useless bits. There is plenty of good info here...

[CSG Mike]

Originally Posted by stugray

If you mean one of those people who have a 2.0L 4cyl boxer engine in two cars a generation apart, then yeah.
My 914 is a lot lighter than my BRZ.... so which one is faster on the track? Might get to find out on my next track day where they both get to go out.



Thanks.

I just want to call out those who say it does not work the way that it DOES work.
YOU CAN go faster by applying the brakes.

In our case, it is absolutely not faster. YMMV.

[TrqlessWonder]

Originally Posted by Sleepless

Nice contribution then...

Seriously, like pretty much an thread of conversation with many people, you have to simply learn to filter out the useless bits. There is plenty of good info here...

We'll have to disagree. The noise is really drowning out the signal around here. And that's quite disheartening.

Somehow, in less than two full pages we went from "Hey guys, I put on some better tires, and right away the traction light is blinking at me, when it never happened before, what's going on?" to someone seeking out and posting a photo of a old trailing arm suspension...just to be an a**hole. And that kind of nonsense is getting pervasive. That's a big heap of garbage to sort through for not much content of dubious quality.

Although, maybe you've got a point. I'm trying to filter out the garbage manually. Perhaps I should let technology help. We have an ignore user function right? I may use that for the first time ever. See if that helps.

[JoeC]

I have heard a couple people on this thread and others around here mention a tank slapper. Is this for real? A tank slapper in a car? I've never heard of that before and frankly it doesn't even make sense to me.

A tank slapper is something that happens on a motorcycle, where the bars are slapping the tank in a high-speed wobble. It escalates pretty quickly. I've had it happen a couple times at really high speeds after setting down a long wheelie. Usually the front tire stops spinning in the air and then has to go from 0 -100+ when you set it down. If you dont set it down just right it can cause a tank slapper. I also have an old honda that needs wheel bearings and it'll do it every time as soon as you take your hands off the bars.

A big one looks like this on a bike:
[ame="https://www.youtube.com/watch?v=v5rhlw_f_FI"]BMW S1000RR Huge Tank Slapper at Knockhill - YouTube[/ame]

Anyway, a tank slapper in car?

[mav1178]

Originally Posted by JoeC

I have heard a couple people on this thread and others around here mention a tank slapper. Is this for real?

[ame="http://en.wikipedia.org/wiki/Fishtailing"]Fishtailing - Wikipedia, the free encyclopedia[/ame]

Fishtailing (also called "tank slapping") is a vehicle handling problem which occurs when the rear wheels lose traction, resulting in oversteer. This can be caused by low friction surfaces (sand, gravel, rain, snow, ice, etc.). Rear-drive vehicles with sufficient power can induce this loss of traction on any surface, which is called power-oversteer.

-alex

[7thgear]

a tank slapper in a car refers to the situation where you try to catch a slide but end up sliding in the other direction and then trying to catch that slide


if you do it wrong by keep adding input (ie, too much counter steer and too much gas or too much brake) you'll end up spinning out completely


although it is common for car drivers to label almost any abrupt state of uncontrollable oversteer as a "tank slapper", but generally some sort of continuous pendulum moment of 3-4 corrections is what I would consider a tank slapper.


watch at the end


[ame="https://www.youtube.com/watch?v=R9MrUk-V_-I"]Mk1 MX5 huge oversteer at Snetterton - YouTube[/ame]

[JoeC]

Originally Posted by mav1178

Fishtailing - Wikipedia, the free encyclopedia



-alex

Originally Posted by 7thgear

a tank slapper in a car refers to the situation where you try to catch a slide but end up sliding in the other direction and then trying to catch that slide


if you do it wrong by keep adding input (ie, too much counter steer and too much gas or too much brake) you'll end up spinning out completely


although it is common for car drivers to label almost any abrupt state of uncontrollable oversteer as a "tank slapper", but generally some sort of continuous pendulum moment of 3-4 corrections is what I would consider a tank slapper.

So people are calling a fishtail a tank slapper... Got it.

They're two totally different things.

[7thgear]

Originally Posted by JoeC

So people are calling a fishtail a tank slapper... Got it.

They're two totally different things.

they are if you're a biker!


Around here tank slapper is used more often than fishtailing to refer to a potential accident situation rather than simply having a loose car that "fishtails a lot"


here's a scary one (you can ff to 0:50)


[ame="https://www.youtube.com/watch?v=9jSYiU-JdRw"]POV Rally Champion Mark Higgins Near Crash at 150 mph @ 2011 Isle of Man TT - YouTube[/ame]

[mav1178]

The reason why it's a "tank slapper" in the automotive world is because as you fishtail, you often will hear the gas tank contents "slap" the tank.

With modern cars this isn't the case, but with older rear-mounted gas tanks (a S13 240SX comes to mind), you can clearly hear the tank being slapped from the inside if you fishtail out of control.

Source: I've done it plenty of times before.

-alex

[Reaper]

im from the motorcycle world and I approve calling an oversteer condition that requires steering from full lock to lock to lock to lock to lock a tank slapper in a car as silly as it seems.


BTW its called that in the motorcycle world because the bars figuratively slap the tank. Not because of fuel slosh.

[Slip Angle]

Originally Posted by CSG Mike

I can reproduce ice mode at will. It is, quite frankly, 100% driver error. If you are inducing ice mode, you're stabbing at the brake, HARD, and are probably deep into ABS engagement.

A lot of drivers use ABS as a crutch instead of a learning tool, and get accustomed to being able to just stomp on the brake pedal in any car, any time, and expect to be able to stop.

Slow down your brake input, learn to properly modulate the brake pedal, and you will never, ever encounter it.

If this continues to be an issue, I will grab some datalogs demonstrating ice mode, and give empirical evidence substantiating the above statements.

I completely agree that it is driver induced. When ice mode occurs, I am going very quickly from the throttle to the brake. I'll work on applying smoother input rather than stabbing at the brake. That said, the issue is certainly real. Especially with aggressive tires and brakes, if you move quickly from the throttle to the brake, the ecu of the car is prone to getting confused and going into "ice" mode which sucks.
It's a reasonable solution then to:
1) do the pedal dance to keep stability control from getting in the way
2) learn to drive around this issue versus going all in on a stand alone racing
brake controller


I do think that ice mode happens even when not stabbing hard enough to get into the abs. It also appears to be happen only when there is steering angle present as it has never happened to me under fast transitions to hard braking in a straight line.


Again, thanks for the help!

[Slip Angle]

Slip Angle is coming from a non-ABS platform and I'm sure that's part of the problem (as I did, the transition wasn't easy for me). It's pretty crappy to drive and think "I need to avoid pissing off my electronics" rather than using the brake pedal as the tool God and physics intended it to be.[/quote]



Well said!

[mav1178]

Originally Posted by mav1178

The reason why it's a "tank slapper" in the automotive world is because as you fishtail, you often will hear the gas tank contents "slap" the tank.

Fixed for you @Reaper


Also:

Tank slapper at slow speed (25 second mark onward)
[ame]http://youtu.be/cGwnf2tyDPA?t=24s[/ame]

Imagine that same sequence, except at 60-80MPH+ and not done intentionally. Induced by snap oversteer, VSC coming on unexpectedly, dropping 2 wheels off the track, or otherwise driver error.

-alex

[dradernh]

Originally Posted by JoeC

So people are calling a fishtail a tank slapper... Got it.

They're two totally different things.

Yeah, I hear you, and given that the car's tank is somewhere in the rear and can't even be seen, it's really hard to slap it like you would on a bike. We try, though, and when we try really, really hard, the effect is a lot like the real thing. Hence, the use of that (admittedly inappropriate) term.