Stability control is not fully defeatable?

[zdr93523]

Pedal dance is the only way to go. The only aid still active is ABS.

[stugray]

FT86 content included:

http://www.cnet.com/videos/car-tech-...als-explained/

And our "E-diff" works by applying brakes to the wheel that is slipping.

[litemup]

[Slip Angle]

Originally Posted by CSG Mike

Pedal dance

Thanks for the link to the pedal dance solution. Great advice...I found a bunch more material on the topic. Thanks to all of you who have responded!

Unfortunately, I'm feeling a sense of deja vu all over again! My friend and I bought Cayman S's in 2007 and ran into the "ice" hard brake pedal and traction control issues. Being a newer car, like the BRZ, there wasn't a lot of data to confirm our problem but it eventually surfaced. My buddy spent tremendous time and money and eventually solved the issue with a BMW Bosch Racing Brake controller..... the same solution that most grand am race teams were using. I sold the cayman and built a spec miata and had a blast for 5 years with that.

Anyway, The BRZ is certainly a great platform but as is the case with other modern cars.... street car safety technology is not track friendly. I've modified the BRZ with better brakes (AP Racing Sprint Kit), coilovers, more aggressive tires and sintered race pads which together, are awesome but are apparently bringing on stability/ brake issues by confusing the ecu?

So what is the best solution? Backing off the brake pads and tires may help reduce the problem but of course, I hate to go backwards. Pedal dance may help the stability control intervention but it sounds like the hard "ice" pedal will still be there. Is there a documented solution that is less complicated than replacing the brake controller with a Bosch system?

Eric

[CSG Mike]

Originally Posted by Slip Angle

Thanks for the link to the pedal dance solution. Great advice...I found a bunch more material on the topic. Thanks to all of you who have responded!

Unfortunately, I'm feeling a sense of deja vu all over again! My friend and I bought Cayman S's in 2007 and ran into the "ice" hard brake pedal and traction control issues. Being a newer car, like the BRZ, there wasn't a lot of data to confirm our problem but it eventually surfaced. My buddy spent tremendous time and money and eventually solved the issue with a BMW Bosch Racing Brake controller..... the same solution that most grand am race teams were using. I sold the cayman and built a spec miata and had a blast for 5 years with that.

Anyway, The BRZ is certainly a great platform but as is the case with other modern cars.... street car safety technology is not track friendly. I've modified the BRZ with better brakes (AP Racing Sprint Kit), coilovers, more aggressive tires and sintered race pads which together, are awesome but are apparently bringing on stability/ brake issues by confusing the ecu?

So what is the best solution? Backing off the brake pads and tires may help reduce the problem but of course, I hate to go backwards. Pedal dance may help the stability control intervention but it sounds like the hard "ice" pedal will still be there. Is there a documented solution that is less complicated than replacing the brake controller with a Bosch system?

Eric

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.

[7thgear]

CGS Mike is gonna go all Takumi on our asses.

[renfield90]

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.

Disagree that it is 100% - say you hit a bump and a front wheel jumps in the air, that could trigger ice mode. That said, changing your braking technique will eliminate nearly all of the problems. Fully agree that too many people use ABS as a crutch to try to brake later and cram the car into the turn.

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.

[Vracer111]

Originally Posted by 7thgear

CGS Mike is gonna go all Takumi on our asses.

You mean Ryosuke...


I wish there was a no ABS option for this car, I would have gone with it...my last 2 vehicles did not have ABS. With the FRS I can feel the EBD system working things out and trying to correct... then I have to correct to the corrections...aaaaahhhhhh! STOP it already and just turn yourself OFF!

[dradernh]

Originally Posted by CSG Mike

If you are inducing ice mode, you're stabbing at the brake, HARD, and are probably deep into ABS engagement.

Will ice mode occur on a smooth, flat section of track when stabbing the brake pedal like a wild man?

[D K]

Originally Posted by Sleepless

System applies brake to wheel off the ground to force the Torsen LSD to transfer power to wheel on the ground; Electronic Differential.

Its not an electronic diff.
The diff has no electronics in it.

An electronic diff is a diff that actually adjusts the lockup.

[CSG Mike]

Originally Posted by dradernh

Will ice mode occur on a smooth, flat section of track when stabbing the brake pedal like a wild man?

Yes... I've actually gone off while trying to reproduce it cuz I actually induced it and just... didn't slow down

[stugray]

Originally Posted by D K

Its not an electronic diff.
The diff has no electronics in it.

An electronic diff is a diff that actually adjusts the lockup.

So what do you propose we call the Twin's version?
It uses: Electronics, an open Diff, and the ABS system to approximate a limited slip diff.

We could call it the: Almost, but not quite, entirely UN-like electronic diff.

Or ABNQEUED

In fact this system could be better than a LSD if the software was smart enough.

[7thgear]

Originally Posted by stugray

So what do you propose we call the Twin's version?
It uses: Electronics, an open Diff, and the ABS system to approximate a limited slip diff.

we have a torsen, not an open diff

Originally Posted by stugray

In fact this system could be better than a LSD if the software was smart enough.

ehh..


when the goal is achieving maximum power delivery, using BRAKES is highly counter-productive

[stugray]

Originally Posted by 7thgear

we have a torsen, not an open diff

ehh..

when the goal is achieving maximum power delivery, using BRAKES is highly counter-productive

I have heard this comment before, and when it applies to braking the wheel that is lifted it absolutely does NOT slow the car down.

Or are you saying that a true limited slip diff slows the car down?

By braking the wheel that is lifting you are applying MORE power to the wheel that is not lifting.
How can that possibly slow the car down?

I suppose letting the lifted wheel spin like crazy (then chirp when it sets back down) is the fastest way around the track??

And I guess using the brakes to stop wheel slip during acceleration (you know "traction control") is also slower than just spinning the wheels.
I guess we need to tell the drag guys they are doing it wrong.