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70% of the force at the rear axle. A number that Tyrone Johnson * does not want to read anywhere. Why? Because she says nothing at all. But we are cool on numbers. Need that, always have to have more than others anyway. PS, zero-to-one hundred, torque, power-to-weight ratio, top speed - higher, faster, farther.
This is how it works with the driving pleasure of the Focus RS
The all-wheel technology of the Focus RS in detail
Therefore also the 70%. Because a supposedly rear-heavy design of the all-wheel drive stands for driving pleasure. That the number is almost fictitious, just so that you have a catchy headline for the press release, which copy all colleagues good, wonderful! Only: what does she really say? Eben: nothing at all.
Because if the mother-in-law in the RS dutifully fetches the rolls, then the fast Ford can be a front-wheel drive. Rear axle? It just follows behind, obediently, because unfortunately it is nailed to the same chassis. But when the young racing driver gets out of the gas while standing on the ice, and a front wheel has just slipped somewhere, then the Ford is normally a rear-wheel drive. Front axle? Unstable, continuous, unusable. Instead, everything goes backwards - and by that we really mean everything. If necessary, only on one side. So: 100% not just at the rear, but 100% on a (!) Rear wheel. Long live freedom! Full variability, always, everywhere. The Ford can do what he wants.
That this does not happen often is mainly due to the traction conditions. Rarely can three tires transmit nothing and a lot. Even less often do you boot so cleanly in such a situation that it would actually activate the 100 / 100 distribution. In general, one has to pay a little attention to the material. 470Nm on a poor cog. At the end of the day, such a Ford is just a delicate compact, not a truck.
If you can not fully understand this, we will help you with a few basics. So this is a little digression into the technology of the all-wheel drive. At least in the Ford Focus RS. Because: not everyone seems immediately clear why the difference to the rest of the world is so great.
The difference to the rest of the “hot hatch world”:
In principle, there are two ways to drive the four wheels, permanently or not permanently. The former is mainly used in the commonly known as "real" Allradlern known and is controlled by a central differential. Non-permanent four-wheel drives then switch the second axle either manually or automatically.
The Focus belongs to the genus of non-permanent Allradler. Although he is actually one. For the front differential is rigidly the power take-off unit (PTU), so the power distributor flanged. This turns with the front differential speed, the propeller shaft and this the rear differential. Whether, however, the two rear drive shafts can really take torque away from the differential, decide on two multi-plate clutch packages. In contrast to the usual Haldex system in this class, in which a hydraulic pump switches a multi-plate clutch into traction when required, the Ford is allowed to operate its two clutches electrically.
And here is the big advantage.
Does the Haldex system about a quarter turn slip on the front axle until the oil pump on the hindquarters has built enough pressure to push the continuous force into the rear, it goes much faster in focus. 100Hz is the frequency with which RS calculates its force distribution - 100 times a second, so what? um, is pretty fast.
100 times a second
But not only that. When the competition Haldex switches then the entire rear axle, the Ford can freely vary the distribution thanks to the two clutches mentioned. Although this makes no difference in the sprint, the RS has no advantage over RS3, Golf R or the 45er AMGs, but the sprint counts only for those who can not drive around the corner anyway.
Anyway, sprint counts only for those who can not drive around the corner
This is where the hour of the performance 4WD arrives. Let's say you have a slow, tight right in front of you. Second gear, apex, full throttle. What happens in a normal “hot hatch”? Not much. The inner wheel will give way and happily go up in smoke instead of generating useful propulsion. In the Haldex hot hatch, the front axle also goes through, briefly, then the clutch switches and the rear axle joins in. But since the inner wheel also has less joy in the curve, the traction level is better, but still not really happy. It is missing: the lock.
Small parts may now add that it is the 45er AMG since its model maintenance with a lock gives, but beware: it sits on the front axle. So what is she doing? Sure, more power on the outer tire on the front. That brings something, but: the rear axle also comes into play accordingly later. After all, the effort shows that a switched axis in the really heavy use of wisdom final is not alone.
Im Focus RS the rear axle runs already before the narrow right and the traction loss of the forehand. Why? Because the Ford has realized that you are shooting and need full effort. So he has his clutches both closed a bit so that it goes as desired forward. Now you rip the steering in, the front axle goes into the corner and the outer clutch on the rear axle closes even more, the inner power on the same extent. The result: more than one limited slip differential. New-German: Torque-Vectoring! All power is well loaded by the driving dynamics on the outer wheel, the RS is sweeping around the bend - who has clicked the ESP in the correct position (Drift), which even reaps a fine oversteer.
Top priority: driving pleasure!
Because that's exactly what Ford was about: driving pleasure. And you do not have it, if it's only in the Haudrauf mode digitally about the bend, but if everything creamy, easy and slightly slips a bit. Again: power oversteer in a compact! That can not even a M135i, because he simply lacks the lock on the rear axle.
But the madness mechatronics in the rear differential of the RS is not the only trick that Ford has installed in the fastest Focus. The translations are still a surprise. That's how it is Rear axle 1.8% translated fasterthan the front axle. That means that the rear wheels - whenever they are active in the smallest percentage - turn 1.8% faster than the two at the front. That tensions the car, as Tyrone Johnson emphasizes. And it's not a marketing blah, it really is. The RS shoots without a hitch, it does not have to shovel any oil into any channels, it is there immediately, immediately across and immediately good.
Incidentally, they did not invent the torque-vectoring system in the "rear drive unit" at Ford. It came from GKN and was first used in the Range Rover Evoque. By the way, the Johnson team borrowed the first prototype diff for the RS. Of course, it did not last a week without crumbling under the steam of the 2.3 Ecoboost engine.
* Tyrone Johnson, the Vehicle Engineering Manager of Ford Performance, the father of the new RS, talked to Tacheles several times during the presentation of the car in Valencia. As a man who already developed Formula 1 cars for the people of Cologne and was responsible for the WRC commitment, everyone should realize that he knows pretty well what he is doing. And if someone like him says that he developed the car purely for driving pleasure off of every stopwatch, then that's wonderful. Because driving pleasure for a real motor sportsman always has something to do with speed. Great speed. So there is no official lap time of the Nordschleife, because it was simply not his goal to meet any paper values. Instead, he is self-confident: who likes, who should measure his RS on the ring. After that the competition. He will not regret it. The fact that he means serious and not overbearing becomes clear at the latest when he says that for him an A45 AMG measured by the chassis and the driving dynamics of the worst car he has driven for a long time. Because such a statement you make in spite of the biggest "balls" not just like that, if you are not really sure and your own car would be breaded in the end.