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We have a limited number of Quaife’s superb differentials for the new Fiesta ST180. – Ideal for those planning to do fast road/track days
This type of differential is also supplied an fitted as standard for the Mk2 RS
Price £710.00 inc vat


 

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Dang too early for this kinda car porn !! wait till after first coffee !! LOL :jawdrop:
 

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What does that do to the cars torque vectoring if you had that in? Would it still try to brake the inside tire on turns?


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From what I have gathered from the FoST people it works well in their case with the T. Vectoring
Bout the only downside is cost and added weight but you get more consistent traction..
 

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What does that do to the cars torque vectoring if you had that in? Would it still try to brake the inside tire on turns?


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From what I've read, the system still functions but due to the diff it's effects are much reduced. Though that is on the Focus ST where the e-diff has to work much harder from the 2.0 having so much torque.
 

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From what I've read, the system still functions but due to the diff it's effects are much reduced. Though that is on the Focus ST where the e-diff has to work much harder from the 2.0 having so much torque.
What if I give my Fiesta a lot more torque to deal with?

I don't think I want to be the one to test this but if it does mess with the vectoring, a front brake upgrade might bring it back.

I hope so any way.
 

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Some of the Focus ST guys have installed these and TVC still works, it's not smart enough to know you have/don't have a LSD installed.
 

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If the torque vectoring uses sensors to control how much it kicks in then it would make sense that it would have less effect with a real LSD in the mix. Therefore it would also make sense that it wouldn't step on the the LSD's toes.
 

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What if I give my Fiesta a lot more torque to deal with?

I don't think I want to be the one to test this but if it does mess with the vectoring, a front brake upgrade might bring it back.

I hope so any way.
I might've stated it a bit misleadingly, I meant that it is fully functional but it has less need to intervene with the braking function to reduce wheel slip. I would guess that for track use it would make a fair difference in lap times by reducing braking heat. Though you lucky people who have STs and have tracked them don't seem to have any brake heat issues. Adding power might be where the LSD diff makes it's benefits felt the most.
 

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The problem is you are going in to a corner, the ESC computer thinks "I need to brake the inside wheel to rotate the car" but the dumb limited slip differential says "I want these wheels to spin at the same rate" and slows down your outside wheel.

Both wheels slow down which means your torque vectoring just slowed you down but it couldn't make the car rotate which was the original idea.

You could make them play well together if the LSD is set up to allow a lot of slip but then is there any point to the LSD? Is a lose LSD any better than just using the e-diff?

Buying one of these is an expensive way to answer those questions so I'll let someone else figure it out before I crack open the transmission.
 

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I am with you on letting someone else find out! Though I would say that torque vectoring is just a LSD emulator, and would likely benefit from a race proven mechanical LSD. Specifically because it would reduce heat fade in the brakes, likely only felt at 10 10ths of the STs capability, which most of us would pucker up and back off before reaching.
 

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Well that is the problem, torque vectoring isn't emulating an LSD, its using the open diff to speed up the outside wheel and rotate the car.

LSDs and the e-diff work by making both wheels turn at the same speed. LSD is dumb, its always on all the time while the e-diff is just part of the program running on your ESC/ABS controller along with your torque vectoring so they work together/don't conflict with each other.
 

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Odd, my understanding was that it uses the outside brake to limit wheel spin, in effect slowing the outside wheel.
 

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I was half right! Lol! Thanks Rod!
 

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You are Welcome and You had it right just thinking outside the box or something... I was still thinking it worked ALL wheels Duh !!! Happy to help I learned something again ... :thumbsup:
 

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Accelerating through a corner the inside wheel is the one that looses traction because the weight load is transferred to the outside wheel and the lightly loaded inside tire will always slip more easily.

Applying brakes to the wheel that isn't slipping would just make the inside wheel spin (slipping) faster which isn't good.

I don't really like what Ford is saying when they say torque vectoring imitates "the effect of limited-slip differential". "Vectoring" implies modulating power to change the direction of the vehicle which would require directional input from the driver, like a steering wheel, accelerometers, etc. E-diff is a simple system that only needs input from the ABS wheel speed sensors.

Slightly off topic ABS has the sole function of keeping your brakes from locking up, traction control has the sole function of stopping the drive wheels from slipping when under power and ESC is an advanced system that identifies and corrects for conditions that would result in a spin or loss of control.

To me thrust vectoring is an amalgamation of driving aid hardware cleverly programmed to alter the handling balance of the car. Its like a fighter jet that's designed to be unstable to increase maneuverability but relies on computers to keep it from crashing because a pilot could never keep up with the reactions of the plane.

Powerful front wheel drive cars are known for torque steer and a handling balance that leans toward under steer, I think torque vectoring is one of the key design features that keeps those poor behaviors hidden. I just don't want to take a chance at screwing it up.
 

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I am really surprised about how much you guys go on and on about "torque vectoring" and "torque steer". For god's sake that was all managed years ago. Civic Sis, Mitsu's, Focus SVTs don't have any real torque steer unless you just have weak fingers on the wheel. I just autocrossed an '04 Focus SVT and don't remember any torque steer, and that's from jumping a hard start and tight corners.
Even my 1996 Mitsu Eclipse didn't have much, if any, torque steer, and that was with a 2.0l, 200 hp turbo...............

The engineers have it handled. 'nuff said.............
 
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