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Discussion Starter · #1 ·
I'm in the market and shopping for a V60. I cross-shopped the Alltrack and found out VW guys with 5th gen Haldex are tuning the diffs to deliver more power to the rear.

Has anyone successfully tuned their haldex? If so, who sells the controller, or is there an SUV controller that we can salvage? How much power have people been able to send to the rear?

Thanks
 

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I'm in the market and shopping for a V60. I cross-shopped the Alltrack and found out VW guys with 5th gen Haldex are tuning the diffs to deliver more power to the rear.

Has anyone successfully tuned their haldex? If so, who sells the controller, or is there an SUV controller that we can salvage? How much power have people been able to send to the rear?

Thanks
No solutions for volvo... Yet.

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Not sure why you'd want to do this, but it may be possible hack it. I think the Haldex unit receives a pulsewidth modulated (PWM) signal at some frequency and voltage from the controller. If so, the signal varies from 0% duty cycle to 100%. If you simply apply a DC signal at the appropriate voltage (probably 14 V), it would be the equivalent of 100% duty cycle, which probably is the command to go to max pressure and lockup.

These cars already do this if the front wheels are slipping.

However, there's no way to NOT send power to the front, so the "best" you can acheive is 50/50. You will never be able to send more to the rear than the front, assuming both are on similar surfaces.

Be careful of the semantics... If the front wheels are on ice and the rears are on dry pavement, the rears will be receiving more torque than the fronts, but that's not what people usually think of when they talk about a "RWD bias" and such.
 

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Discussion Starter · #4 ·
The goal is to deliver more of a push- handling feel rather than pull- handing feel, with maybe a bit more throttle steering (I'm not holding my breath).

Sorry to hear there's no answer, I was hoping the VW solution would be easy to translate over. Thanks for the quick answer
 

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The goal is to deliver more of a push- handling feel rather than pull- handing feel, with maybe a bit more throttle steering (I'm not holding my breath).

Sorry to hear there's no answer, I was hoping the VW solution would be easy to translate over. Thanks for the quick answer
The polestar haldex has this ability but apparently it is not compatible with any other S60.
 

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Can you explain how this is done?
Curious myself. I didn't know about this.

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To answer my own question, I learned that it is possible to achieve a rear-biased torque split on an FWD-based architecture like ours by employing a slightly "taller" gear ratio in the back. This can be done either in the transfer case or the rear diff.

So this is a "hardware" solution, not software.

Is this what Polestar did??
 

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Can you explain how this is done?
I have absolutely no idea, just reading the press release. I'm assuming it's like the Golf R tunes.

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To answer my own question, I learned that it is possible to achieve a rear-biased torque split on an FWD-based architecture like ours by employing a slightly "taller" gear ratio in the back. This can be done either in the transfer case or the rear diff.

So this is a "hardware" solution, not software.

Is this what Polestar did??
Let me see if I understand what you're saying. Front ratio is 3.21, for example, and the rear has a 2.93 gear ratio? I suppose this makes sense although I would imagine this would be tough on the Haldex unit.

By this logic, we could employ a "Haldex hack" by under inflating front tires and over inflating rear tires (changing rear circumference to be larger than front).



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Let me see if I understand what you're saying. Front ratio is 3.21, for example, and the rear has a 2.93 gear ratio? I suppose this makes sense although I would imagine this would be tough on the Haldex unit.
Yes, that is correct. The little bit of interweb research I did indicates that the Focus RS does this. Yeah, it would be hard on the Haldex, but 1.) the Haldex is not engaged 100% of the time and 2.) you'd have to design the Haldex system (or similar thingy) with this in mind. You might end up adding a cooler, thicker discs, more pressure, etc.
 

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All SPA series Volvos have the ability to transfer more than 50% torque to the rear wheels through the Polestar tune.
Can you explain how this is done?
I’m assuming this is a Volvo software choice controlling torque allocation to favor more of a rear bias. In the VW world people interested in getting more of a sporting rear bias would get an upgraded Haldex controller which I’m assuming is a little black box that made this possible. I wonder if such a thing can be retrofitted to our cars?
 

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If the front and rear gear ratios are the same, they will equally share engine output torque (i.e., 50/50) when the Haldex is locked solid.

Software reprogramming can make the Haldex lock a little earlier and/or harder, but without a gear ratio change, it can't send more than 50% to the rear because it cannot REDUCE torque being sent to the front.
 

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Yes, that is correct. The little bit of interweb research I did indicates that the Focus RS does this. Yeah, it would be hard on the Haldex, but 1.) the Haldex is not engaged 100% of the time and 2.) you'd have to design the Haldex system (or similar thingy) with this in mind. You might end up adding a cooler, thicker discs, more pressure, etc.
This jives with what I recall from the early days of the Focus RS where people were overheating the rear differential and having to install aftermarket coolers (https://www.roadandtrack.com/new-ca...rs-need-to-know-about-the-2017-ford-focus-rs/)
 

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I'm in the market and shopping for a V60. I cross-shopped the Alltrack and found out VW guys with 5th gen Haldex are tuning the diffs to deliver more power to the rear.

Has anyone successfully tuned their haldex? If so, who sells the controller, or is there an SUV controller that we can salvage? How much power have people been able to send to the rear?

Thanks
Id like to throw out there that during my misadventures with my haldex system, i saw the VWAG logo on the pump. I wonder if volvo sourced their haldex systems from VW
 

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I'm in the market and shopping for a V60. I cross-shopped the Alltrack and found out VW guys with 5th gen Haldex are tuning the diffs to deliver more power to the rear.

Has anyone successfully tuned their haldex? If so, who sells the controller, or is there an SUV controller that we can salvage? How much power have people been able to send to the rear?

Thanks
Hi I’m not sure how it could be done and how much you will spent but exemple, if you have a v60 2012/ I know that the s60 2018 polestar (like the real one) not the polestar engineered can put 70% to the rear/30% to the front when they are on sport mode….
 
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