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Torque Vectoring in the Rain

7556 Views 27 Replies 10 Participants Last post by  juliog
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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Exactly why I was asking if he tried it with the system fully off. :)
Thanks for the clarification. I feel like I had some misinformation on the systems but this makes it more clear.

However, I still experienced oversteer in wet conditions. And it wasn't the lift throttle oversteer I've come to love.

I've done well with sport mode but will see what happens with lap times next season with esc off.
It could have just been trail braking in general that induced snap over steer in the rain. Depending on the conditions and how you did it, that could have the same outcome in a 100% analog car.
So, there's an old rally technique that was used on front wheel drive cars; both pedals.
The problem being addressed is that most front wheel drive cars understeer. Applying power in a corner only makes understeer more, So while accelerating out of a turn, the brakes are applied lightly. This has a gyroscopic effect on the front wheels, which in turn causes the rear wheels to break away, allowing a front wheel drive car to four wheel drift. The angle of the car in the turn can be adjusted by applying more or less brake to tighten or loosen the line. I used to use this in my old VW Rabbit on sweepers in the rain. .. Has anyone tried it with ESC fully on, or in Sport mode?

I mentioned it to instructors at OA and they acted like they had never heard of it (too young?), but also said "no trail braking" even tho they did it themselves.
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So, there's an old rally technique that was used on front wheel drive cars; both pedals.
The problem being addressed is that most front wheel drive cars understeer. Applying power in a corner only makes understeer more, So while accelerating out of a turn, the brakes are applied lightly. This has a gyroscopic effect on the front wheels, which in turn causes the rear wheels to break away, allowing a front wheel drive car to four wheel drift. The angle of the car in the turn can be adjusted by applying more or less brake to tighten or loosen the line. I used to use this in my old VW Rabbit on sweepers in the rain. .. Has anyone tried it with ESC fully on, or in Sport mode?

I mentioned it to instructors at OA and they acted like they had never heard of it (too young?), but also said "no trail braking" even tho they did it themselves.
If I'm understanding you correctly it sounds like you are talking about left foot braking, lightly applying the brakes mid corner to transfer more weight to the front and break traction in the rear. In short, yes this works very well in this car, I have only been able to do this at an autocross but this car rotates wonderfully with a little bit of left foot braking. Around a decreasing radius sweeper a quick stab at the brakes mid corner and a flick of the wheel and you can feel the rear end wiggle, break loose then come around nicely.


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Yes, ... left foot braking. (during cornering). I'm assuming ESC off since your were autocrossing?
Yes ESC was off, definitely hard to maintain grip in first gear with a stage one tune, I spin the tires all the way through that gear.


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DSC is for the unable.

Left foot braking is nice in the FiST. I use it all the time on my rally roads. Such a fun and capable car this thing is out of the box.

I prefer driving DSC off at all times and in the rain when doing solo runs. Just drive more conservatively in the rain and drive with understeer in mind, not oversteer.

I will leave DSC on when commuting on highways, that's it.
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Factory alignment and Porterfield r4-s pads up front only.
Very likely that's causing the ABS system to act up. Rear tires slowing down at a slower rate may cause ABS to think your front tires are sliding.
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