[12_Ice_white_S60]

I was making a left turn this morning on dry pavement, and nailed it from a standstill. To my surprise the inside front tire chirped for quite some time before I felt either the torque vectoring or rear wheels start pushing.

I would have expected that the fronts would not have spun given that Gen 4 is supposed to be 50/50 from a standstill.

 

[baggerben]

Funny you bring this up. Yesterday I was going - let's say faster than I should have,and the front end pushed badly. To the point of engauging the dstc. I know from a standstill and slamming the gas pedal down,this thing just squats and takes off. I guess it is what it is.

 

[Copper_s60]

Ive noticed the same, nail it in a turn and you get wheel chip, but straight line, zooom...

However, in geartronic sport mode, I noticed its less likely to occur.

 

[geokilla]

So I understand that while Haldex may have many different levels of AWD systems, how "bad"is the one in the S60 compared to the one that Lamborghini uses? Note the quotes on bad. It's obviously a dumb, stupid comparison, but just wondering how similar the systems are, if there are any similarities at all. Is the S60 the most basic one produced by Haldex? If it is, that would explain why it was ranked last in the Car and Driver comparison. Slow to react and engage + heavy weight = not a fun driving experience compared to the other vehicles in that comparison test.

 

[Copper_s60]

For me its great at highway speed. Bad is a strong word. its good just quriky in certian slower situations imo

 

[teefive]

I don't have an S60, but fwiw, if I nail the throttle in the two other full time 4wd cars in my family (X5 4.4 xdrive and Grand Cherokee Hemi) I'll get a touch of wheelspin in the inside wheel when turning.

When turning and accelerating, the front inside wheel is unloaded as weight shifts to the opposite corner of the car. A little traction loss in a high torque engine shouldn't be surprising. A grippier tire may help out.

 

[merlot]

So I understand that while Haldex may have many different levels of AWD systems, how "bad"is the one in the S60 compared to the one that Lamborghini uses? Note the quotes on bad. It's obviously a dumb, stupid comparison, but just wondering how similar the systems are, if there are any similarities at all. Is the S60 the most basic one produced by Haldex? If it is, that would explain why it was ranked last in the Car and Driver comparison. Slow to react and engage + heavy weight = not a fun driving experience compared to the other vehicles in that comparison test.

Lamborghini does not use Haldex. They use an in house viscous traction system which is completely different.

 

[geokilla]

Lamborghini does not use Haldex. They use an in house viscous traction system which is completely different.

http://www.roadandtrack.com/tests/car/2012-lamborghini-aventador-lp700-4. Many other sites say they use Haldex as well.

Like the Murciélago, there are three drive mode settings (Strada, Sport and Corsa) that dictate three separate parameters: shift aggressiveness, steering effort and, unlike the Murciélago, all-wheel-drive character. In Strada mode, the Haldex IV all-wheel-drive system is tuned for mild understeer, has the lightest steering effort and the "smoothest" shifts (relative, of course). Power distribution is more rear-biased in Sport, with an increase in steering weight and quickening of shifts. In Corsa, the Haldex is set up for maximum performance, which means quickest power transfer, the heaviest steering feel and most aggressive shift strategy. Take a hairpin turn in this mode and you'll feel the front wheels pull you through the corner. The Murciélago, on the other hand, had a simpler fixed ratio system that worked fine on the track, but didn't offer the flexibility or safety for all driving scenarios. Aside from slow, tight corners, the all-wheel-drive system is nearly invisible, and it allows for obscenely high drift angles.

 

[Copper_s60]

Slighly off-topic,

apparently there's a tuning company selling re-tuned haldex ecus for VWs. Thought that was interesting itself as i though the engine ecu controlled that.

One could dream of a more rear-ward bias setup for the S60... hehee

 

[MagoonR]

Yesterday I was going - let's say faster than I should have,and the front end pushed badly. To the point of engauging the dstc.

All the gizmos and AWD will still have a difficult time compensating for a 62/38 weight bias.

 

[merlot]

http://www.roadandtrack.com/tests/car/2012-lamborghini-aventador-lp700-4. Many other sites say they use Haldex as well.

Interesting.. I have not yet read about the Aventador, but prior models used the viscous sytem. I stand corrected.

 

[Stefan1235]

Slighly off-topic,

apparently there's a tuning company selling re-tuned haldex ecus for VWs. Thought that was interesting itself as i though the engine ecu controlled that.

One could dream of a more rear-ward bias setup for the S60... hehee

No, it's been tried over and over in the R forum, but no large company can legally adjust Volvo's haldex control unit because Volvo owns all rights to the software and will not let anyone change and mass produce it. A local Russian tuning company managed to adjust the haldex gen III for a "500hp S60R from Russia", so it's possible BUT only if you go local and put down a lot of money.

 

[Street_Volvo]

No, it's been tried over and over in the R forum, but no large company can legally adjust Volvo's haldex control unit because Volvo owns all rights to the software and will not let anyone change and mass produce it. A local Russian tuning company managed to adjust the haldex gen III for a "500hp S60R from Russia", so it's possible BUT only if you go local and put down a lot of money.

It is not a software control, its just direct hardware management of Haldex electrical schemes.

 

[kova]

I was making a left turn this morning on dry pavement, and nailed it from a standstill. To my surprise the inside front tire chirped for quite some time before I felt either the torque vectoring or rear wheels start pushing.

I would have expected that the fronts would not have spun given that Gen 4 is supposed to be 50/50 from a standstill.

Obviously eLSD used by Haldex 4 system isn't still working as it should..

 

[Copper_s60]

Obviously eLSD used by Haldex 4 system isn't still working as it should..

Volvo does NOT use eLSD. They use torque vectoring on front wheels only.

 

[kova]

Volvo does NOT use eLSD. They use torque vectoring on front wheels only.

Does it? And what would exactly be the difference between "torque vectoring" and electronic brake based LSD?

 

[Copper_s60]

Does it? And what would exactly be the difference between "torque vectoring" and electronic brake based LSD?

marketing not to mention hadlex eLSD works on the rear axle.

 

[kova]

Precisely - only marketing..

Electronics obviously fails to detect wheel spin to apply brake. They would be better off with mechanical LSDs like in Impreza.

Mechanical LSDs are quicker then central diff so they have a chance to rectify the wheel spinning problem distributing axle torque to the wheel with more grip. Only when it fails central diff should redistribute torque between axles, and when it fails the ECU should cut torque.