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Discussion Starter · #1 ·
Dear all. I mentioned this in my Sonoma post but thought it deserved its own topic.

I had some scary experiences thanks to the TV in wet conditions. Specifically turn 11 which is a tight hairpin.

With breaking in a straight line the car is more predictable, but with trail breaking on accelerating out of the corner, TV kicks in and induces oversteer.

In dry conditions, the back wheel remains fixed and acts as a pivot point. In wet conditions, it behaves like an e-brake turn. A warning to any road racers out there.
 

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ESC does not equal TVC...TVC is constant...ESC can be turned off
 

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Discussion Starter · #9 ·
I think we are all saying the same thing.

TV was on, regardless of ESC status. And it was TV that caused the car to act unpredictably in a low speed but sharp turn in wet conditions. I was just seeing if anyone else has had that experience and offering a warning as it could have spun the car if I didn't correct.
 

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Not in the rain but my car sometimes will wiggle a little bit under hard corning while trail breaking for me it was a learning curve and I tryed to avoid it after the first big wiggle or squirm and just braked straight and harder then off and into the corner with throttle.. weird feeling to say the least. wish McRib would get back and try out the Brake Module from Ford racing..
 

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I think we are all saying the same thing.

TV was on, regardless of ESC status. And it was TV that caused the car to act unpredictably in a low speed but sharp turn in wet conditions. I was just seeing if anyone else has had that experience and offering a warning as it could have spun the car if I didn't correct.
How do you know for certain if you didn't try it with ESC fully off?
 

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Not in the rain but my car sometimes will wiggle a little bit under hard corning while trail breaking for me it was a learning curve and I tryed to avoid it after the first big wiggle or squirm and just braked straight and harder then off and into the corner with throttle.. weird feeling to say the least. wish McRib would get back and try out the Brake Module from Ford racing..
As I have stated before, my FiST does not exhibit any of those characteristics under trail braking, it's totally solid, no wiggles unless I do something to upset the chassis (like any normal car). However it might be because of my upgraded brakes and alignment settings.

That is basically what I am getting at here. Cars do different things depending on alignment settings. That's why alignments are a HUGE part of the chassis tuning process. Even brake compounds front to rear have a lot to do with how the chassis reacts to trail braking.

OP, what are your alignment settings?
 

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Discussion Starter · #13 ·
Factory alignment and Porterfield r4-s pads up front only. I ordered the rear pads because the last track day finished the stock ones off with 8000 miles on them. That may effect the front rear braking balance.

Interestingly, the right rear brake pad wore out before the left, because my home track, Sears Point, runs clockwise.
 

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Factory alignment and Porterfield r4-s pads up front only. I ordered the rear pads because the last track day finished the stock ones off with 8000 miles on them. That may effect the front rear braking balance.

Interestingly, the right rear brake pad wore out before the left, because my home track, Sears Point, runs clockwise.
It would be interesting to see what your alignment is. Mine was all wack from the factory. Crazy toe, which does crazy things at the limit. ;)

btw, you should look into some camber bolts for the front and dial in some more negative camber, makes a world of difference, especially if you keep tracking the car.
 

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I think you are talking about the EDiff in the Fiesta. TV acts on the inside rear wheel.
Uhhmmm..., you're not correct here. The Torque Vectoring affects the FRONT (drive) wheels only. There is no "EDiff". The TV functions by applying "some" brake force to the spinning wheel which transfers "some" of the torque to the other side. Quite simple and effective for the most part. The Torque Vectoring function can NOT be disabled. The Electronic Stability Control (includes traction control and slip angle control) however, is the system that may apply a front AND/OR rear brake to correct accelerometer-sensed slip angle, and/or modulate the throttle to eliminate front wheel-spin in relation to the rear (traction control). The ESC has 3 user-selectable modes; "On", "Sport", and "OFF". The Sport mode allows more wheel-spin before it modulates the throttle and the OFF mode, well the entire system is simply OFF.

I have tried out the ESC modes in autocross competition (class winning, not also-ran) and I can tell you that the ESC should be completely OFF for best results, regardless of surface conditions. With the ESC in Sport mode, the car "feels" more stable and wheel-spin is reduced, but the car is much slower when measured with the unblinking timing clocks. The clocks don't lie, so turn the ESC fully OFF and drive the car.

Oh yeah, my measured wheel alignment was spot-on from the factory. -1.2 front camber, -0.7 rear camber with 3/32 toe-in front and rear.
 
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