How does our Quattro System work?

[imported_ZeroK66]

Hello all,

So how does it work? Does the 1.8 2.x & S4's have different versions?

Do we have any form of traction control? And does the system split power between the front & rear dependant on traction? What is it normally... 75/25 split?

Thanks,
Leon

 

[AndyMac]

You have permanent 4 wheel drive (the traditional Quattro system with traction control) whereas the A3 has the Haldex system (with traction control). The Haldex system is mostly FWD, until its needed. There's a post on here somewhere explaining exactly how both systems work

 

[K212]

You sure its permanent 4 wheel drive? Or is there a difference with Euro versions versus US versions?

 

[AndyMac]

Yeah they did a special version just for the americans, it only kicks in in the unlikely event you have to negotiate a corner

 

[jdp1962]

[ QUOTE ]
AndyMac said:
Yeah they did a special version just for the americans, it only kicks in in the unlikely event you have to negotiate a corner

[/ QUOTE ]

RAOTFLMAO!!! /ubbthreads/images/graemlins/laugh_roll.gif

 

[K212]

[ QUOTE ]
AndyMac said:
Yeah they did a special version just for the americans, it only kicks in in the unlikely event you have to negotiate a corner

[/ QUOTE ]

Man... once again, US restrictions limits vehicle performance..

 

[aagallarini]

The S4s have ESP (Electronic Stability Program) that seems to work via the anti-lock braking system. It's pretty effective and flashes a little light in the tach when it's working. It seems to transfer all of the strain to the clutch though, as I've had the clutch slip a few times when ESP was forced to activate. I don't know exactly how Quattro works though, and would like to know myself. Please post back here if you find an good explanation of it, especially on the S4.

 

[neil.c]

The larger audis have a "torsen" or torque sensing centre differential, the a3 having a haldex electronic centre diff.
Do a search for torsen see what you find.

 

[K212]

[ QUOTE ]
neil.c said:
The larger audis have a "torsen" or torque sensing centre differential, the a3 having a haldex electronic centre diff.
Do a search for torsen see what you find.

[/ QUOTE ]

This is directly from the Audi website dated October 2002:

If the drive forces are distributed evenly to all four wheels from the outset and unrestricted engine speed compensation is assured, the result is an optimum propulsive effect. This is made possible by the use of an interaxle differential. Various different technical solutions are available, though Audi supplies easily the most elegant concept. At Ingolstadt, they have created a unitary torque-sensitive, or Torsen, differential in the form of an interaxle differential. This refined device incorporating worm and helical gears always diverts power to the point where it achieves the greatest effect, in other words to whichever pair of wheels achieves the better grip. Conventional differentials, on the other hand, tend to divert the power to the spinning wheels. Audi's Torsen system is available on the A4, A6, A8 and allroad.

 

[qA4Blake]

Our system during normal driving is a 90/10 split. I have also had some clutch slippage during slightly high launches and hard turns. Instead of a wheel turning over or the car loosing traction, the clutch takes on the burden almost like a traction control would. Not fun stuff.

 

[aagallarini]

[ QUOTE ]
qa4blake said:
Our system during normal driving is a 90/10 split. I have also had some clutch slippage during slightly high launches and hard turns. Instead of a wheel turning over or the car loosing traction, the clutch takes on the burden almost like a traction control would. Not fun stuff.

[/ QUOTE ]
This is where I would rather have the ESP system act on the timing and fuel in addition to the ABS, just to save the clutch. I have a hard enough time turning the Bridgestones over with all the torque sensing stuff going on! All I can ever seem to get is a little 'squeek' when I have ESP off and launch hard.

So is there only 1 torsen LSD (in the center) or 2 or 3?

 

[imported_ZeroK66]

here is the full explanation... this is how our system works and why it is sooo good! NICE!

http://www.ukcar.com/features/tech/traction/Torsen.htm

 

[neiloneilo]

[ QUOTE ]
http://www.ukcar.com/features/tech/traction/Torsen.htm

[/ QUOTE ]

/ubbthreads/images/graemlins/crazy.gif

 

[aagallarini]

I take it my S4 has 2 torsen LSDs then, one in the rear and one in the center. It is difficult to read and still difficult to see how it works with just mechanical drawings. I'd like to see video of it in action. To me the drawings make it seem that it's an over-complicated posi unit than an LSD. I'm missing where the sides are allowed to turn at different speeds. All the worm gears/wheels seem to lock the whole mechanism together.

 

[K212]

I'm still trying to figure out them formulas... /ubbthreads/images/graemlins/smile.gif

 

[imported_ZeroK66]

Seems like a manual "yaw control"... that is what makes it good.

I dont really understand it, but I am much happier having read that to know that we have true 4wd!

 

[neiloneilo]

I agree, does anyone know of any video/animated examples?

 

[imported_ZeroK66]

Black... you dont have this system ony our car? Or do you own an A4 too?

 

[dummi]

do S3's have haldex then or torsen??

i heard the props and drive shafts were very similar on the a4 to the s3, i am probably wrong, just wanted to know if anyone else heard that

Ds

 

[imported_Osinyou]

so let me get this straight the uk version has perminate 4wd but the us version has awd that rear kicks in when needed. that is quite a disappointment for us usa drivers. Man that is lame.

 

[imported_ZeroK66]

S3 does not have the full quattro system. Those cars with transverce mounted engines have haldex eh: S3, golf 4motion etc and so FWD till traction lost.