Alright, so now I'm more confused than ever. I've seen several articles on the R saying that up to 100% of the power can go to the rear wheels (including the dealer pdf thread here). I've also seen vw docs that contradict this, like http://media.vw.com/release/750/ That says 50% to the rear wheels. I've seen "how it works" videos on YouTube that show it somewhere between the two, but don't state specifically. So, what's the real answer? How much power can get to the rear axle on the R, and what's your source? I'm looking for more technical documentation instead of magazine reviews that just repeat vw press material that may be incorrect.
4motion/Quattro
Kretrop
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Alright, so now I'm more confused than ever. I've seen several articles on the R saying that up to 100% of the power can go to the rear wheels (including the dealer pdf thread here). I've also seen vw docs that contradict this, like http://media.vw.com/release/750/ That says 50% to the rear wheels. I've seen "how it works" videos on YouTube that show it somewhere between the two, but don't state specifically. So, what's the real answer? How much power can get to the rear axle on the R, and what's your source? I'm looking for more technical documentation instead of magazine reviews that just repeat vw press material that may be incorrect.
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4motion is not the same as Quattro
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Haldex in its current generation can vector 100% of torque to the rear.
You have to understand that 4motion and Quattro are trade names for all wheel drive. The actual systems in the VW and Audi models are different and depend on the chassis and configuration. Therefore, their capabilities all differ.
For example, on the B8.5 S4, you have the crown gear center differential on some cars and the traditional Torsen center differential on others. And both systems have a default 40/60 split.
The R has a Generation 5 Haldex system.
You have to understand that 4motion and Quattro are trade names for all wheel drive. The actual systems in the VW and Audi models are different and depend on the chassis and configuration. Therefore, their capabilities all differ.
For example, on the B8.5 S4, you have the crown gear center differential on some cars and the traditional Torsen center differential on others. And both systems have a default 40/60 split.
The R has a Generation 5 Haldex system.
Also keep in mind that the capability to have 100% of the power to the rear means nothing if the real world can never provide a situation to the computer where 100% rear power would actually help maintain stability or control.
These systems can probably do many cool things in a lab, but I doubt the car will ever feel the need to put all power in the rear in a stock setup.
Its just a stat they can give so every you tube review can mention it. (I have not heard any mainstream car journalists omit this little tidbit yet).
These systems can probably do many cool things in a lab, but I doubt the car will ever feel the need to put all power in the rear in a stock setup.
Its just a stat they can give so every you tube review can mention it. (I have not heard any mainstream car journalists omit this little tidbit yet).
It's TORQUE not power. That is different.
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This
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Which is the same system referred to as Quattro in the A3/S3....
The transverse engine chassis use the Haldex system for 4Motion/quattro (Golf R, A3/S3, TT)
The longitudinal engine chassis use the more traditional quattro applications (A4, A6, A7, A8, etc)
Does that help?
No ****? :screwy: :banghead:
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It depends on the installation.No ****? :screwy: :banghead:
4Motion is not the same as traditional longitudinal quattro, but it is the same as transverse quattro...see my post above.
that's not entirely correct, unless you're saying the words are different, because in that case, they are not the same.
Golf R with 4 motion and an S3 with Quattro have EXACTLY the same 4wd system, with different names.
Audis with longitudinal engines and quattro, have a center diff, in which case they are mechanically different.
but then you get into the Touareg 4motion, and now that's basically the same as the longitudinal version of quattro.
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Bottom line is that these are marketing terms, not specific technologies.
I know this. I was just pointing out how useless the posters post was that I quoted.
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When the title of the thread is 4motion/Quatrro it leads one to believe the original poster views these as the same, which they are not...simply clarifying in the event he has that view. Thanks for over reacting and keeping the vortex forum boards safe :thumbup:
They are the same in the R and the S3. The cars are mechanically identical. I don't really care about any other applications; that's why I asked specifically what the R does. (It's also the same system in the Euro market Golf 4Motion, which you can get on non R models, and all A3/S3 Quattro. Same exact system.)
Some VW docs say up to 50%. Some say up to 100%, all relating to this car, not other applications. I reached out to Jake Holmes of Automobile Mag (his was one of the few articles I saw that said 50), and he was kind enough to follow up with their US VW PR rep, who confirmed it's 50, and initial translated literature was incorrect in saying 100. So, again, we have discrepancy. To those saying 100: what is your source?
I'm trying to separate marketing from reality in the case of the R (and, by extension, the S3). I want to know the actual torque split in this application. I have my doubts that it can go 100% RWD.
Torsen (longitudinal engine layout)
"quattro" = Audi A4-A8, R8, Q models
"4Motion" = VW Touareg, Phaeton, Passat (B5)
Haldex (transverse engine layout)
"quattro" = Audi A3, TT (always based on VW Golf platform)
"4Motion" = VW Golf R, Passat (B6 and later), CC
So yeah, it's not about what the AWD system is marketed as, it's which technology is used based on the engine layout. IIRC, Torsen cannot be used on a transverse layout. In the future, as the VW Group fully incorporates the MQB (transverse) and MLB (longitudinal) platforms, it should be even more straightforward which AWD tech goes with which vehicle.
Also, the Gen 5 Haldex allows the rear to be de-coupled when not needed (highway cruising) to increase fuel economy.
"quattro" = Audi A4-A8, R8, Q models
"4Motion" = VW Touareg, Phaeton, Passat (B5)
Haldex (transverse engine layout)
"quattro" = Audi A3, TT (always based on VW Golf platform)
"4Motion" = VW Golf R, Passat (B6 and later), CC
So yeah, it's not about what the AWD system is marketed as, it's which technology is used based on the engine layout. IIRC, Torsen cannot be used on a transverse layout. In the future, as the VW Group fully incorporates the MQB (transverse) and MLB (longitudinal) platforms, it should be even more straightforward which AWD tech goes with which vehicle.
Also, the Gen 5 Haldex allows the rear to be de-coupled when not needed (highway cruising) to increase fuel economy.
in the physically impossible case of 0 friction and 0 drivetrain loss at the front tires (thus requiring no torque to spin), the rears would in fact receive 100% of the torque. in the opposite case where all wheels have infinite grip and you stomp on the gas, the torque split will be an even 50/50.
It's both. The Haldex is not a diff, it's a computer controlled clutch between the trans + front diff and the rear diff.
See http://www.billswebspace.com/HALDEX.pdf
When the clutch is completely engaged (no slip), both front and rear diffs receive 100% of engine power. When the clutch is disengaged, no power goes to the rear diff.
At no time does more power go to the rear diff than the front diff.
So the rear diff can get 100% of the engine's power (while the front is also getting 100%). If having that add up to 200% bothers you, divide by 2.
Sometimes 4motion and quattro ARE THE SAME depending of the vehicle and naming.. Hence, part of my frustration. But thanks for being a know it all who obviously doesn't know ****
It's very simple as others have stated, Quattro and 4Motion are branding names for AWD under VW/Audi. They change in design slightly from generation to generation but if the same platform is shared between the models (IE MK7 Golf & A3) it uses the same system.
The Haldex diff Gen 5 works with the XDS+ managing torque placement. If your standing still and both front tires have zero traction (like if your stuck on ice) it can send 100% of the torque to the rear wheels, that is the only way it can send that much torque to the rear. XDS+ uses the brakes to actually stop the front wheels/axles completely and the torque finds its way the the path of least resistance, AKA your rear tires. While all 4 wheels are in motion it will not be able to send more than 50% of the power to the rear though. Does that make sense?
The Haldex diff Gen 5 works with the XDS+ managing torque placement. If your standing still and both front tires have zero traction (like if your stuck on ice) it can send 100% of the torque to the rear wheels, that is the only way it can send that much torque to the rear. XDS+ uses the brakes to actually stop the front wheels/axles completely and the torque finds its way the the path of least resistance, AKA your rear tires. While all 4 wheels are in motion it will not be able to send more than 50% of the power to the rear though. Does that make sense?
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