AWD Systems

[oneseba]

Not sure if this was covered before but I've noticed on paper Quattro is not as savvy as other competitor offering (xDrive and SH-AWD). Even the upcoming Quattro Torque Vectoring is said to be copying the new xDrive system on the to be released X6. Both systems btw can send torque between rear and front axles and send torque to individual rear wheels (lateral) via electronic sensing, initiated by breaking the slipping wheel. SH-AWD has had this since 2004 but using a dual clutch rear differential controlled by electromagnet and along with an accelerator managed by an ecu which sends torque appropriately based on slippage. What's going on with Audi? Maybe somebody shed light on these systems technically. Not trying to bash Audi here, just want to know how they all stack up against each other. Also hopefully no brand loyal emotionally-charged responses

[MYDWAGON]

Audi is the best. http://www.youtube.com/watch?v=5ki7rs0RvBE

[oneseba]

Old systems.

[B18b1ex]

Old systems.

Call it old but it is simple, and for the most part mechanical, thus less to go wrong.

[B18b1ex]

Audi is the best. http://www.youtube.com/watch?v=5ki7rs0RvBE

The one you posted does not have the allroad it was cut.

Here you go.
http://www.youtube.com/watch?v=8zfKRdgoRo4&NR=1

Any questions why should be answered with it works, and works the best.

[oneseba]

Call it old but it is simple, and for the most part mechanical, thus less to go wrong.

Which makes the A4 a pig.

I'm looking for a technical discussion here. I know it works because it uses open differential front and back with EDL. EDL detects slippage and applies brake to the spinning wheel to force transfer torque to the opposite, torque transferred is dependent on ratio. This makes Quattro great in snowy conditions. However if there is no slippage at all (zero traction, ice or wheel in air) no torque will be transferred at all, if this happens on the rear the e-brake might be able to save you. But in normal road conditions, say turning, this causes understeer because of the front bias weight and the 50:50 distribution. This what the BMW Dynamic xDrive and SH-AWD offers and hopefully the new Quattro Torque Vectoring system will accomplish. All these systems are integrated with the vehicle's stability control, abs, traction control and this is where I get stuck, putting the pieces together. Hoping to get some input from our more technically apt members

[m5racer]

i have driven my moms 07 328xi in the snow and my car in the snow, honestly noting beats quattro. The xi has a ton of tire slippage in the snow and doest grip as well ie. mroe tire spin.

[AudiA4_20T]

Not sure if this was covered before but I've noticed on paper Quattro is not as savvy as other competitor offering (xDrive and SH-AWD). Even the upcoming Quattro Torque Vectoring is said to be copying the new xDrive system on the to be released X6. Both systems btw can send torque between rear and front axles and send torque to individual rear wheels (lateral) via electronic sensing, initiated by breaking the slipping wheel. SH-AWD has had this since 2004 but using a dual clutch rear differential controlled by electromagnet and along with an accelerator managed by an ecu which sends torque appropriately based on slippage. What's going on with Audi? Maybe somebody shed light on these systems technically. Not trying to bash Audi here, just want to know how they all stack up against each other. Also hopefully no brand loyal emotionally-charged responses

to be honest with you, I believe Audi is the best.

1. My freinds dad has an Acura RL AWD and his dad couldnt get up his smooth stone driveway in the snow. I could

2. My other friend has an STI, I was driving very conservatively with him last winter but he couldnt keep up with me in the snow (I had full traction it was not a race, just regular driving)

[itsdarrow]

^ that may have more to d with the tyres no??

[m5racer]

yes, reguarless what specs say on paper Quattro works the best. in a snowfall that was over 1 ft deep i was able to get past everything on the road + it was impossible to get suck anywhere.

Example:Stock sport suspension on 16' wheels: went into a fesh driveway and no one had driven in before let the pics do all justification. Basicaly i got in stopped took the pics got back into the car, and jsut like in any normal summer day drove away, didnt need to rev engie to get out and there was zero wheel spin. i barly realized i was driving in that much snow, except for the fact that mad shit was rubbing the bottom of the car as i drove around the city that morning.

Snow was plowed as i opend the door



quattro = amazing

xi in similar conditions would have a ton of wheel spin and the car would slide around and drift. it was actually had for me to drift in my car, both cars had brand new winters

[Videlov]

yes, reguarless what specs say on paper Quattro works the best. in a snowfall that was over 1 ft deep i was able to get past everything on the road + it was impossible to get suck anywhere.

Example:Stock sport suspension on 16' wheels: went into a fesh driveway and no one had driven in before let the pics do all justification. Basicaly i got in stopped took the pics got back into the car, and jsut like in any normal summer day drove away, didnt need to rev engie to get out and there was zero wheel spin. i barly realized i was driving in that much snow, except for the fact that mad shit was rubbing the bottom of the car as i drove around the city that morning.

Snow was plowed as i opend the door



quattro = amazing

xi in similar conditions would have a ton of wheel spin and the car would slide around and drift. it was actually had for me to drift in my car, both cars had brand new winters

I agree, Audi does have the best AWD system out there. I get so excited when it snows, just makes my day, I look for snow like this ^ to go an have some fun :)

[AudiA4_20T]

^ that may have more to d with the tyres no??

YGPM, at least I think I sent it... lol

[4ringAR]

ok, first off let me say that tires play a HUGE part in how well a car will perform in adverse weather.

that said, from what I have read Audi's torsen AWD and some of Subaru's AWD systems are the BEST AWD systems available. They are purely mechanical so there are no computers and electronic variables that have to "think" before they give you traction.

Through logic I have come up with the following: In theory these systems might help keep the average driver on the road in adverse conditions, but knowing how your car will react 100% of the time is better for a more experienced driver.

And now through experience let me tell you how great Audi's torsen AWD system is. I have driven up steep driveways with 12" of fresh snow on it, and then gone through the 2+ foot snow plow berm(and vise versa) not getting stuck. I have driven on sheer ice of a frozen lake, and not been stuck. Because there were no electronics in my car telling it which wheels to send the power to, i knew EXACTLY how my car was going to react with the imputs I gave it while going around the track on the frozen lake. All on all-season tires. The only time I can remember not being able to drive any further forward in snow was in the picture below. (it was like a 4 foot deep snow plow berm into almost as much in fresh snow)

[mxrz]

There is AWD and then there is AWD. quattro is great in adverse weather, it's an all wheel drive system made for safety. However, in terms of on road performance, it is fairly inferior to Nissan's latest version of ATTESA ET-S for example, which has been developed, from the ground up, for road performance... not snow and such.

[4ringAR]

There is AWD and then there is AWD. quattro is great in adverse weather, it's an all wheel drive system made for safety. However, in terms of on road performance, it is fairly inferior to Nissan's latest version of ATESSA ET-S for example, which has been developed, from the ground up, for road performance... not snow and such.

though you can say the same about audi's normal torsen AWD, and the torsen AWD on the R8. Clearly the R8 is built for track performance, not all-weather performance.

however, i find having the "performance" AWD as a factor in this discussion given that the OP was saying xDrive and what not are technology savvy.

[B18b1ex]

Which makes the A4 a pig.

I'm looking for a technical discussion here. I know it works because it uses open differential front and back with EDL. EDL detects slippage and applies brake to the spinning wheel to force transfer torque to the opposite, torque transferred is dependent on ratio. This makes Quattro great in snowy conditions. However if there is no slippage at all (zero traction, ice or wheel in air) no torque will be transferred at all, if this happens on the rear the e-brake might be able to save you. But in normal road conditions, say turning, this causes understeer because of the front bias weight and the 50:50 distribution. This what the BMW Dynamic xDrive and SH-AWD offers and hopefully the new Quattro Torque Vectoring system will accomplish. All these systems are integrated with the vehicle's stability control, abs, traction control and this is where I get stuck, putting the pieces together. Hoping to get some input from our more technically apt members

First of assmonkey you don't know me, so lets not make stupid assumptions.

You are such a dumbass that somehow you equate the the fact that the Quattro system is mechanical and simple, and that somehow makes it a pig. The mass of the car and it's distribution is the only thing that affect the A4's handling.

If all four wheels are on ice then the system applies the brakes to control wheel spin to obtain the best traction available, if they all spin then they all get the same power (please remember even on Ice you have some traction). BTW if all of these cars are put on a sheet of ice which do you think will do the best.

You got stuck putting the pieces together because you as I stated before are a dumbass, the only difference between the systems you named are the electronic clutch in the center differential, but they all use the abs brake sensors and brakes to control wheel spin and transfer power. The quattro just does it mechanically, when the brake is applied the power is transfered.

[B18b1ex]

For all that want to criticize the handling of the Quattro, realize the system works well, too well for most motorsports sanctioning bodies to allow. And when they are allowed they have many restrictions and penalties.

Audi compromises the placement of the engine and drivetrain for their designs, maybe this is changing with the new models we will see as they continue to evolve.

[bob12312357]

I know the Audi Quattro is better then the Evo in snow, but for performance driving the Evo's AWD would spank an Audi's the 51 weeks of the year there isn't 2 feet of snow. 06 EVO= best AWD system I've ever driven for performance.

[B18b1ex]

I know the Audi Quattro is better then the Evo in snow, but for performance driving the Evo's AWD would spank an Audi's the 51 weeks of the year there isn't 2 feet of snow. 06 EVO= best AWD system I've ever driven for performance.

Of course you are free to make such a blanket statement because the two companies do not compete the same series, but no one can deny Audi's racing background and accomplishments.

[bob12312357]

^^^^
I don't rally race in snow, or in mud on the street. So for performance driving 51 weeks out of the year where i live, I'll take an Evo thank You, now if only their price fell like a brick like an Audi's does when u pull away from the dealer.;)