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The new Golf R is getting a torque-vectoring AWD system similar to the Juke, with a clutch for each rear wheel. And it will be offered with a manual. Not sure if this AWD system will be spread to other models...

"The new torque-vectoring 4Motion AWD uses two individual clutches in the rear-drive unit to vary torque distribution between the rear wheels and it’s possible to transmit up to 100% to a single wheel, said Schafer. A maximum of 50% of total engine torque can be apportioned to the rear axle."

 

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I'm so freaking bored with VW's styling but man this sounds like a fun car. It's what the Nismo Juke should've been from the factory. A legit hot hatch. 315hp? Yes please.
 

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The VW gulf... has not changed much. Nor the 911 really. But the 911 is a classic, and does not need to really.
The gulf, well it would be nice to see something different. Maybe thats the market they are going for, the folks that want a sleeper.

Honda and its ATTS is a nice system. Would love to see more of that. Only on the 5th gen prelde, the RDX, and the RL. Why not on an AWD hot hatch. I think they would do well.
 

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Discussion Starter #4
If they stuck this drivetrain in the next generation T-Cross, made the styling less boring, and brought it to the US, I would definitely be taking a look.
 
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Naw.... I don't plan on owning a contemporary german car. As I do not want to work on it. Well built but a slightly different school of thought when the conceive them and put them together.

But has the gulf, ever looked like something that just jumps out at you?
LINK to the wiki. I just took a look and none of them really jump out at me.

They don't need to do much either.
 

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The new Golf R is getting a torque-vectoring AWD system similar to the Juke, with a clutch for each rear wheel. And it will be offered with a manual. Not sure if this AWD system will be spread to other models...

"The new torque-vectoring 4Motion AWD uses two individual clutches in the rear-drive unit to vary torque distribution between the rear wheels and it’s possible to transmit up to 100% to a single wheel, said Schafer. A maximum of 50% of total engine torque can be apportioned to the rear axle."

Sounds very similar to the Juke, with the addition to brake torque vectoring as well.

Having said that, not necessarily will it make for a great AWD system. It still lacks the front/center locking differentials that say an EVO has, which already has it's own SAYC or yaw control. Coming off of that, the Juke system is almost primitive by comparison though effective in it's very narrow operating band. Primarily, these vectoring systems require the electronics to drop the car in and out of AWD mode, thus the part time FWD. This is good in the dry mostly, where conditions are not changing all that rapidly and the computers/sensors can keep up. Also, the full time locked AWD-mode can't be deployed efficiently 100% of the time in the dry because there is a ratio differential front and rear that causes high slippage rates in the drivetrain due to the Torque vectoring requirements.....thus you get serious heat build up in the rear clutch packs. The rear-end is over-driven by about 2%, similar to the Focus RS. Thus, you have to run part time AWD which is basically FWD until the computer detects wheel slippage. Very funky handling that torque vectoring, and fairly creepy in a high speed corner. It works, but most guys don't drive an AWD hard enough to really know what the torque vectoring feels like. Think over-steer and vehicle roll-over all in-one, not exactly confidence inspiring. I get non of that in my EVO except safe neutral turn-in, though you can kick the rear end out doing something stupid. In the wet, the Juke is not so good because the electronics can't engage AWD fast enough for it to make a difference. And this is the Juke's AWD achilles heal, mostly an electronics problem. The EVO has no such deficiencies as it's a combination of a highly evolved SAYC or active yaw system plus a couple of mechanical diffs thrown in..

The Juke AWD system is essentially a bunch of compromises. Not so great with understeer in wet/snow, can't really run full lock AWD in the dry either for long periods of time, Torque vectoring is a scary senstation in high speed corners though effective in killing understeer in the dry. Better than FWD, no contest against a real AWD system.

Definitely a huge step forwards but I think to get a world class AWD system such as the EVO or GTR you need to buy something like the Yaris GR with the additional track package and additional locking differentials so see how insane a system like that really can be. I will even say that the RS 6spd where it counts the mechanical front LSD in many ways covers a lot of the gaps the standard Juke AWD has. Where you need to kill understeer, it's tough to beat an physical mechanical LSD, under all conditions. AWD is nice, but an RS with winter tires would be 95% as effective and in some ways IMHO it would be better as the AWD understeer in the snow is insanely bad.

Torque vectoring is amazing technology, but mainly was used to augment an already well balanced AWD system. The current crop of AWD systems are leveraging it too heavily in an attempt to simplify the AWD mechanicals, and I think that's a big mistake.

Food for thought.
 
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Here's an additional technical writeup on the Haldex 4-motion AWD system. The EDS and XDS systems use brake torque vectoring, primarily to fake a limited slip differential.
The Haldex system then decides the front/rear wheel split using a single clutch pack integrated in the rear differential, I believe hydraulic actuated.
Basically, the Haldex clutch pack is in the rear differential, with the rear left/right wheels simply using the brake rotors to torque vector the left/right split.


EVO-X AWD:

OK, so the EVO X utilizes a helical limited slip "front" differential, a single clutch pack computer controlled hydraulic actuated helical "center" differential (front/rear bias), and (2) computer controlled rear clutch packs with another helical limited slip planetary "rear" differential, plus brake torque vectoring on all (4) wheels.

 

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Discussion Starter #8 (Edited)
Sounds very similar to the Juke, with the addition to brake torque vectoring as well.

Having said that, not necessarily will it make for a great AWD system. It still lacks the front/center locking differentials that say an EVO has, which already has it's own SAYC or yaw control. Coming off of that, the Juke system is almost primitive by comparison though effective in it's very narrow operating band. Primarily, these vectoring systems require the electronics to drop the car in and out of AWD mode, thus the part time FWD. This is good in the dry mostly, where conditions are not changing all that rapidly and the computers/sensors can keep up. Also, the full time locked AWD-mode can't be deployed efficiently 100% of the time in the dry because there is a ratio differential front and rear that causes high slippage rates in the drivetrain due to the Torque vectoring requirements.....thus you get serious heat build up in the rear clutch packs. The rear-end is over-driven by about 2%, similar to the Focus RS. Thus, you have to run part time AWD which is basically FWD until the computer detects wheel slippage. Very funky handling that torque vectoring, and fairly creepy in a high speed corner. It works, but most guys don't drive an AWD hard enough to really know what the torque vectoring feels like. Think over-steer and vehicle roll-over all in-one, not exactly confidence inspiring. I get non of that in my EVO except safe neutral turn-in, though you can kick the rear end out doing something stupid. In the wet, the Juke is not so good because the electronics can't engage AWD fast enough for it to make a difference. And this is the Juke's AWD achilles heal, mostly an electronics problem. The EVO has no such deficiencies as it's a combination of a highly evolved SAYC or active yaw system plus a couple of mechanical diffs thrown in..

The Juke AWD system is essentially a bunch of compromises. Not so great with understeer in wet/snow, can't really run full lock AWD in the dry either for long periods of time, Torque vectoring is a scary senstation in high speed corners though effective in killing understeer in the dry. Better than FWD, no contest against a real AWD system.

Definitely a huge step forwards but I think to get a world class AWD system such as the EVO or GTR you need to buy something like the Yaris GR with the additional track package and additional locking differentials so see how insane a system like that really can be. I will even say that the RS 6spd where it counts the mechanical front LSD in many ways covers a lot of the gaps the standard Juke AWD has. Where you need to kill understeer, it's tough to beat an physical mechanical LSD, under all conditions. AWD is nice, but an RS with winter tires would be 95% as effective and in some ways IMHO it would be better as the AWD understeer in the snow is insanely bad.

Torque vectoring is amazing technology, but mainly was used to augment an already well balanced AWD system. The current crop of AWD systems are leveraging it too heavily in an attempt to simplify the AWD mechanicals, and I think that's a big mistake.

Food for thought.
I wouldn't be sure about it not working well. When I was at SAE WCX a couple of years ago, I spoke to one of the Honda engineers at their booth about the new SH-AWD, which quietly switched from a complex arrangement of gears to a simple clutch-based system, similar to the Golf-R, GKN Twinster, or Juke system, but with hydraulically controlled clutches. I asked about it and how they could offer continuous torque to the wheels. He said that the AWD system actually had more torque capacity and higher reliability due to the dramatic improvement in mechanical simplicity, which enabled more advanced material use. The reduced mechanical complexity of the clutch-based system actually reduced losses in addition to weight. He said that they tested the systems back to back in test mules and the lighter new system with more aggressive torque vectoring easily beat the old system in performance testing... Can't remember the numbers now, but I was impressed. Of course, there may be some bias.

189476


That said, just as electronic fuel injection has overtaken carburation, software controlled systems will perform better, if they do not already. Software, sensors and systems have improved dramatically in the past decade and are not slowing down. I never thought torque vectoring was a "scary" sensation, but I come from RWD cars with a tendency to oversteer... slow in, fast out. However, changes in programming can alter a car's balance to your taste and to the application. Realistically, I think old-school mechanical AWD systems are on their way out, like it or not. Electrified systems like the GKN E-Twinster or Nissan's new AWD e-power (or what's used in the MacLaren P1 or LMP1-H) just have too many advantages in putting torque where it needs to be uninterrupted with reduced losses. Software-dependent mechanical systems like the Golf-R are likely a stopgap.
 

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Discussion Starter #9
Here's an additional technical writeup on the Haldex 4-motion AWD system. The EDS and XDS systems use brake torque vectoring, primarily to fake a limited slip differential.
The Haldex system then decides the front/rear wheel split using a single clutch pack integrated in the rear differential, I believe hydraulic actuated.
Basically, the Haldex clutch pack is in the rear differential, with the rear left/right wheels simply using the brake rotors to torque vector the left/right split.

The new Golf-R does not use that system. It is a new system more like the GKN Twinster. The EVO uses a system somewhat similar the the previous-generation SH-AWD, which is outdated if you listen to Honda.
 

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Ine937s,

I haven't driven it, but yes that is the 2015 model and not the new system.

The software/programming is really the trick. The Juke AWD really needs some improvement here. The EVO X have it down to a science, basically an AI is driving the car and you would never know it when driving one. The EVO X and the S-AWC have proven themselves in earlier WRC and various latter Rally categories with privateer teams running the EVO X. The GOLF R never set foot on a WRC rally stage. If 12 years later somehow it's better, well it's about time. In reality, I already know the previous GOLF R was really hamstrung by the traction control......same as the Juke AWD. That previous Golf R was put against an EVO X on a head-head comparison on a road course and was totally crushed, mainly due to an overly intrusive traction control system which could not be totally de-activated. The EVO X traction control is actually there to make you faster and save your life. So it's tough to deploy an AWD when the computers are stepping in at full tilt. The EVO X has no such limitations, the driver's aids simply made the car faster under all conditions.

You cannot disassociate the traction control, abs, and AWD systems these days as they are fully integrated. The Juke ABS is so bad it's comical, the VDC also frustrating, while the AWD is quite good. But it's the entire package that matters under varying driving conditions. They are not in full harmony. I'm not going to parse the differences between electro-hydraulic, electro-magnetic, clutch vs torsen vs brake vectoring. Every manufacturer has a different AWD system and it matters more how it's deployed. Honda can say this or that, means nothing. Prove it on the track, on a rally stage and I'll believe it. The Yaris GR and full track package is running (2) torsen mechanical LSD diffs all around, which is because it's intending on competing in WRC. It is yet to prove itself, but the early indications are that it will be damned impressive, even if it doesn't win any WRC championships. I'd take that setup 100 times over a GOLF R for the reasons I stated. It would totally destroy it.

I'm not stating don't buy a GOLF R, but be realistic. I was actually considering it but the VDC issues were a deal breaker, it wasn't even the Haldex system.

Here is some EVO X in WRC Group N form. Although the cars seem slow, it's because the AWD system is so clamped down, and of course the power is limited in Group N as well so it won't look like a WRC car. Again, never designed for WRC but amazing they could still get out there and rally. The +3500 lb curb weight and long wheel base aren't really WRC material, it was designed as an BMW M3 competitor but very cool that the S-AWC can still show it's stuff on the dirt.

 

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On older models with haldex there is a ton of aftermarket support & options. As the complexity rises, support and customization would be my question. The awd in the juke appears to function seamlessly, but the difficulty in dynoing and the limitations of the cvt accessibilty/customization have been a huge disappointment.
It's not really fair to compare my previous experiences with a 2000 audi tt manual with haldex vs the juke awd cvt, as the systems and vehicle types are totally different, but the TT was on rails. The juke feels like a lifted truck in comparison. Neither ever broke traction, even with both tuned (apr stg 1 vs ecutek stg 1) but the cvt kills the experience on the juke. If a golf r had good tuning options (which is expected) and the awd system has some adjustability like a haldex does, then it could be a worthwhile tuned vehicle for the money.

Edit: vehicle styling aside... Golfs have always been bland imo.
 
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