RS4 Quattro system question

[5000S old skool]

does the 40/60 torque split change to 50/50 if necessary in in the wet/bad weather?

[clam]

I suspect not. It's probably a modification of the mechanical diff, and being mechanical, it probably isn't adaptable.
It should do well in bad wether. The classic Quattro system suffers from understeer. The benefits from the improvements will also be felt in bad conditions.

That video of the RS4 going up the slope says it all. Imagine any other car trying that.

We really need to get some in-depth information on this car. So many questions...

[5000S old skool]

There has to be some way to make the split 50/50 in certain conditions. Maybe a manual setting? I just cant imagine an Audi not neing better than other AWDs in snow/rain/sand etc..

[Ebx]

It's a Torsen, so it should be perfectly capable of transferring torque where it's needed. The press release for the RS4 also says it is self-locking, doesn't it? That would mean a real 50:50-split anyway, right?

There's more information about the Torsen here, I'm guessing the RS4 will be the first Audi to use the T-3 version.
http://www.torsen.com/products/T-3.htm

[5000S old skool]

nice...

[clam]

50/50 is not ideal. While cornering, the front tyres have to do a lot more work than the rear ones (unless you slide through the corners rally style). They have to slow the car down, and make it change direction, while the rear tyres kinda drag behind.
It's the reason why FWDs are limited as performance cars. Here the front tyres have to do all the work.
It's also the same reason why a 42/58 rear biased weight distribution is said to be ideal, instead of the 50/50 many people think.
And, it's the reason for rear biased AWD. (Lamborghini, Porsche)

The 50/50 distribution ideal, both power and weight, comes from straight line performance, and the tricks they use in AWD motorsport (like the Scandenavian flip, left foot braking) to handle the corners. But in real everyday driving, a rear biased distribution is more useful.

Another big advantage is being able to controle the slip angle of the rear tyres (induce oversteer), independently from the front. This allows the driver to find the perfect balance, using the steering wheel (for front control) and the throttle (for rear control). This isn't possible with a 50:50 split, since the wheels don't act independently.
40:60 is not as "pure" as RWD, when it comes to controling oversteer, but the additional traction should make up for that.

to sum up, 40:60 means:
*a better balance between the forces the tyres have to translate
*a better control of the car

It wouldn't surprize me if the RS4 manages to pull 1G on the skidpad. Or at least close to 1G.

[5000S old skool]

ok, now im convinced :0:

[Erik]

Originally posted by clam
It wouldn't surprize me if the RS4 manages to pull 1G on the skidpad. Or at least close to 1G.

This is not skidpad. With the new 255 wide wheels and DSG it will be better for sure.


Transverse Acceleration

Maximum G-Force 1,15 g
at Speed 167 Km/h

http://www.track-challenge.com/