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"the Focus manages without a mechanical differential, relying instead on a smart torque-vectoring system that uses traction control software to brake a spinning wheel. The result, slightly improbably, is the most phenomenal grip."

Just curious if anybody is at all concerned by the lack of a mechanical differential? What do you suspect would happen to the cars steering in the event of a major, electrical malfunction at high speeds?
 

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In not really concerned about that. My concern would be faded brakes at auto cross or road course events due to the use of the brakes as a limited slip.
 

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If you're concerned about the lack of mechanical differential, wait for the Focus RS. It was excluded from the ST to keep costs down, and for 99% of what the ST will be used for, the torque vectoring system will be sufficient.
 

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"the Focus manages without a mechanical differential, relying instead on a smart torque-vectoring system that uses traction control software to brake a spinning wheel. The result, slightly improbably, is the most phenomenal grip."

Just curious if anybody is at all concerned by the lack of a mechanical differential? What do you suspect would happen to the cars steering in the event of a major, electrical malfunction at high speeds?
your question about steering at high speeds doesn't jive with the differential related comment. If you are worried about losing EPS at high speed, you should take heart that EPS based cars have existed for decades. If you are worried about losing your synthetic diff at high speeds, I don't really understand why.
 

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In not really concerned about that. My concern would be faded brakes at auto cross or road course events due to the use of the brakes as a limited slip.
This is my biggest concern as well. I've seen what stability management can do to an outside drive wheel's rotor and pad. UG-LY. And fast, too.

I can't imagine that in all but the most rigorous of track situations trying to shave time off (read: not for fun anymore), would you really need the mech. LSD.

Although it could come in handy in autoX apps, too.
 

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A mechanical LSD like a Torsen or Quaife is what this car really needs. If you like to drive spirited expect to be replacing brake pads and rotors often as you will feel the brakes pumping when you're making turns or going down windy-twisted roads.

Take some time with your new car. You can always buy a Quaife or Torsen around $1000-$1500. I hear they're a pain in the ass to install so if that's true you should check into what the labor will cost.
 

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If I were going to do regular autocross with the ST, I'd mod it for larger disks. MUCH larger disks. Autocross seems like something you do with a junk car fixed up, not a brand new one you drive every day. But for racing, if your brakes are doing double duty, you need more overhead in the front brakes than the ST comes with.

As far as changing rotors and brakes more frequently because you're racing it...you guys are joking, right? Changing rotors and brakes is about the simplest maintenance thing you can do with a race car. If you're not racing it, likely you won't be engaging the brake torque vectoring that often. If you're racing, you want it because it brakes the inner wheel in hard turns (also known as brake steering) to minimize understeer. Right when you need it. Straight->hard brake to turn entry->rear oversteer->hard acceleration to straighten the car out and pull out of the turn at the apex. You don't want that front end washing just when you're at the hardest lateral acceleration point.

I think McLaren's use a similar, though likely more refined system.

In any case, if you race, expect increased maintenance. If you're serious about racing, expect to do some redneck engineering in the garage. Also, expect to crack the control automation to reprogram the LSD system for different conditions for optimal racing performance, as well as the electronic power steering assist. I've mentioned before that in my day, you raced, you changed/modded EVERYTHING. And you spent a crap ton of money doing it. Even with a pushrod engine, changing cams was a PITA, and you changed pistons, modded heads for better breathing, changed carbs and manifolds, ignition, put on blowers, changed/modded shocks, springs, roll bars, brakes, gear ratios, exhaust...you completely re-engineered everything about the car.

And I've watched autocross and track days. Almost everyone is a LOT slower than they are in their own heads :)

So I think even for the recreational racers, stock probably will be just fine. Unless you're Tom Cruise, Cameron Diaz, Matt LeBlanc, Rowen Atkinson, or Brian Johnson. If you are, make sure you have a friend with a fire extinguisher to put out your flaming brakes :)
 

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A friend of mine has a willwood setup on his Camaro SS that have quick release/install entry points so that you can replace the pads at the track in minutes and put in a dedicated race set. The Rotors are also Hats that are easily replaced and less expensive.
 

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If I were going to do regular autocross with the ST, I'd mod it for larger disks. MUCH larger disks. Autocross seems like something you do with a junk car fixed up, not a brand new one you drive every day. But for racing, if your brakes are doing double duty, you need more overhead in the front brakes than the ST comes with.

As far as changing rotors and brakes more frequently because you're racing it...you guys are joking, right? Changing rotors and brakes is about the simplest maintenance thing you can do with a race car. If you're not racing it, likely you won't be engaging the brake torque vectoring that often. If you're racing, you want it because it brakes the inner wheel in hard turns (also known as brake steering) to minimize understeer. Right when you need it. Straight->hard brake to turn entry->rear oversteer->hard acceleration to straighten the car out and pull out of the turn at the apex. You don't want that front end washing just when you're at the hardest lateral acceleration point.

I think McLaren's use a similar, though likely more refined system.

In any case, if you race, expect increased maintenance. If you're serious about racing, expect to do some redneck engineering in the garage. Also, expect to crack the control automation to reprogram the LSD system for different conditions for optimal racing performance, as well as the electronic power steering assist. I've mentioned before that in my day, you raced, you changed/modded EVERYTHING. And you spent a crap ton of money doing it. Even with a pushrod engine, changing cams was a PITA, and you changed pistons, modded heads for better breathing, changed carbs and manifolds, ignition, put on blowers, changed/modded shocks, springs, roll bars, brakes, gear ratios, exhaust...you completely re-engineered everything about the car.

And I've watched autocross and track days. Almost everyone is a LOT slower than they are in their own heads :)

So I think even for the recreational racers, stock probably will be just fine. Unless you're Tom Cruise, Cameron Diaz, Matt LeBlanc, Rowen Atkinson, or Brian Johnson. If you are, make sure you have a friend with a fire extinguisher to put out your flaming brakes :)
This is about correct. Although my concerns were more in regard to casual track days/autoX. My points of reference are to other stability management systems that are transparent enough to make it seem like you're a badass, while actually destroying your outside drive wheel (or sometimes outside front wheel in severe understeer situations).

PSM comes to mind first. I can't tell you how many Cayman and Boxster owners had a rude awakening upon defeating the system.

I guess part of my question is, does turning off the stability management on these cars defeat torque vectoring too? Or is that a non-defeatable system. And as a follow up, how much single-wheel braking interference is actually occurring if it *isn't* defeatable?
 

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I was under the impression that the system Ford is using on the ST actually brakes the inside wheel, which would make sense since the weight is transferred in a turn to the outside wheels, where you'll have superior traction. And effectively tries to make the car pivot around that front inside wheel.

Anyone know if I have that correct?

Why would traction control actually destroy a wheel?
 

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I was under the impression that the system Ford is using on the ST actually brakes the inside wheel, which would make sense since the weight is transferred in a turn to the outside wheels, where you'll have superior traction. And effectively tries to make the car pivot around that front inside wheel.

Anyone know if I have that correct?

Why would traction control actually destroy a wheel?
Not the wheel itself, but the brake rotor and pad. Have to ask an engineer about exacts (and I ain't one), but constant actuation of the brake(s) while cornering is a recipe for a LOT of excess heat. Think about what happens when you leave a parking brake on and drive. Sort of the same concept, with a much different execution.
 

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Frankenbike you are spot on!!

im not worried in the least. One may burn up pads and rotors quicker than most, especially if your tracking the car. If one is tracking the car brakes are going to get trashed anyways along with tires. Part of paying hard.
 

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Frankenbike you are spot on!!

im not worried in the least. One may burn up pads and rotors quicker than most, especially if your tracking the car. If one is tracking the car brakes are going to get trashed anyways along with tires. Part of paying hard.
I'm guessing you meant "Part of playing hard" But "paying hard" seems appropriate too!
 

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yep, let me fix that. ahh forget it. proof reading is something i should consider.
 

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Not the wheel itself, but the brake rotor and pad. Have to ask an engineer about exacts (and I ain't one), but constant actuation of the brake(s) while cornering is a recipe for a LOT of excess heat. Think about what happens when you leave a parking brake on and drive. Sort of the same concept, with a much different execution.
Oh, I agree, it'll destroy brakes and rotors. If you've ever raced, this is unbelievably trivial as far as expenses and racing goes. An immense bargain if it does what it says it does considering the competitive advantage you'd have.
 

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For the fairly limited range that MOST of us will be testing this is a great compromise of effect versus cost. They are using an already in place ABS to double duty as a fakey LSD. Brake pads are something that I really don't care about wearing faster, and as others have said unless your are tracking it, its essentially a non worry point.
It would save front end ( a little ) weight too. Most importantly in the cost of the car... it saves money.
 

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Oh, I agree, it'll destroy brakes and rotors. If you've ever raced, this is unbelievably trivial as far as expenses and racing goes. An immense bargain if it does what it says it does considering the competitive advantage you'd have.
I wasn't talking about full-blown sanctioned racing, but yes, you are correct. Will be interesting to see.

FWIW, I had lord knows how many track hours on my last car, and remarkably was able to keep pads about 20K miles per front set. Tires only lasted about 7-8K, though. :)
 

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Well, the tires will cost more than the brakes, if that's any consolation.

Maybe you'll be the first to report how long the brakes last to the rest of us with your frequent track days. Someone has to be first :)

When you replace them, I suggest giving carbon-Kevlar brakes a try. They tend to be easier on rotors and wear more evenly while taking a crap-ton of heat.

I see numerous brake/pad threads in the future for this forum.
 
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