[solid7]

I have been trying to study the differences between the full-time AWD systems used in some of the longitudinal engine placement platforms, to the Haldex Quattro systems used in the transverse engine platforms. Unfortunately, it's all academic, as I don't have the two in front of me. What I'd really like to know is, how can I get to full-time AWD in a system that uses a Haldex?

I have seen a couple of threads about "stuck" Haldex controllers, making unintentional full-time AWD. Some posters claim that the Haldex would have cooling issues in full-time mode. However, it's just an unsubstantiated claim, from what I can see. (not saying that it's incorrect, just not backed with fact - just hypothetical discussions, with no real concensus)

So, let's consider this... I have a project, which doesn't need to be identified by a particular vehicle. In other words, I have a lot of freedom to do as I please, without the constraint of an OEM configuration. So... How do I get from an MK4 VW Golf/MK1 Audi TT driveline, to a full-time AWD system? Is it possible to swap components (like the rear differential) from the longitudinal full-time AWD driveline? Is it possible to hack the Haldex to be stuck in full-time mode?

Thanks in advance...

 

[JamesS]

http://www.sqsracing.com/produkt/314:406:haldex-regulator-controler-valve

 

[solid7]

http://www.sqsracing.com/produkt/314:406:haldex-regulator-controler-valve

I'm assuming that you know this product through ownership? I cannot understand the broken English description... I think it's saying that you can turn the rear differential on or off before you start the car. (?)

 

[JamesS]

You need to search. If you are installing haldex in a transverse platform then you need to control the haldex differential which can be done with the controller I linked or by other standalone controllers which operate the differential and shift power as needed. Maximum is 50% to the rear, can be variable or even LOCKED 50/50.

Generally speaking, you can't mix and match a longitudinal differential with a transverse engine/transmission.

 

[solid7]

You need to search. If you are installing haldex in a transverse platform then you need to control the haldex differential which can be done with the controller I linked or by other standalone controllers which operate the differential and shift power as needed. Maximum is 50% to the rear, can be variable or even LOCKED 50/50.

Generally speaking, you can't mix and match a longitudinal differential with a transverse engine/transmission.

Sorry, I did do a search. Maybe I'm not searching the right way, or something. I get a lot of threads where people are just talking, and nobody seems to be agreeing.

I have a transverse setup right now. From what I've seen, it doesn't look like I'm going to be able to alter the behavior to be locked 50/50, but that's why I'm asking... I just don't know.

I did get a nice conversation going with Daryl at HPA, so I'm learning a bit more. And no disrespect to him at all, but his focus is on controlling the hardware in the intended setup, and I'm willing to venture outside of that. But I will definitely consider all info equally.

 

[JamesS]

It is pretty easy to get the transverse to lock 50/50. Two methods:

1. Standalone controller
-you can just set the controller to 50/50.

2. The SDS controller I linked
-just turn the knob to engage the rear differential fully


Since the system isn't designed to run 50/50 all the time I would keep an eye on temperatures or add an external fluid cooler.

 

[solid7]

It is pretty easy to get the transverse to lock 50/50. Two methods:

1. Standalone controller
-you can just set the controller to 50/50.

2. The SDS controller I linked
-just turn the knob to engage the rear differential fully


Since the system isn't designed to run 50/50 all the time I would keep an eye on temperatures or add an external fluid cooler.

So that's great info, but I don't know much about standalone controllers. Is that something that can be incorporated into a standalone engine management system, or are you referring to a controller like the HPA?

 

[JamesS]

It is standalone in the sense that the controller can operate the differential without integration with any other system. Totally different than the HPA controller which operates within CAN bus.

 

[BrewDude]

Haldex isn't meant to be engaged all the time. As one user found out after buying this insert which basically locks the valve into providing pressure to the clutch packs full time, the plates are now burned out rendering the Haldex useless. He thinks it has to do with different brands of tires (no mention of size), I think he's being naive about it.

http://forums.vwvortex.com/showthread.php?6132138-Your-Haldex-Works-Powertrak-Insert-Review

 

[solid7]

I read that whole thread. Unfortunately, it's another of those threads with a lot of discussion, no concensus, and a bit of commercial bias thrown in. Lots of naysayers, but every successful product or idea ever developed, has had its critics and detractors along the way. Where most people see problems, there are always a few who see only challenges, waiting to be overcome. Even if it's been tried and failed a million times, that doesn't mean that it can't be done. (I'm a former R&D engineer, who has seen many long standing design issues solved by persistence, gained experience/knowledge, and fresh perspectives)

When I said I wanted "full-time AWD", this guy moto135 really captured the essence of what I was after, even if his results were not altogether faborable. And basically, for me, that is to get away from another complicated and expensive electromechanical sub-system in the car. (which is one of my biggest dislikes of this platform)

Turning the AWD on and off at will is awesome. I like that. Maybe 100% AWD is not ideal, and I can see why, from some of the other points made in that thread.

Couple of questions to ponder...

Can the heat issue be solved by adding an oil intercooler to deal with haldex fluid temps?
Has anyone ELSE found a way to replace the haldex controller with a more mechanical system, in the same vein as moto135? (if so, what were your results?)

Seems like a switch and relay to engage the controller/solenoid, coupled with a break switch in the shifter (since reverse is a down plunge motion) would be quite simple to do... Would make quick work out of the binding in reverse issue. But what exactly is responsible for the binding issue in the rear differential, to begin with? Afraid that I've missed that point.

 

[JamesS]

Translate this to english:

http://www.haldex-performance.de/de/haldexsteuerung/haldexsteuerung-mk3-professionell-6bar

This is what you want to meet your goals.


This is a cheaper option:
http://www.ebay.de/itm/Haldex-Steue...492977?hash=item3d0822a3f1:g:d9gAAOSwq7JUJ8Q5

 

[ticketed2much]

Haldex isn't meant to be engaged all the time. As one user found out after buying this insert which basically locks the valve into providing pressure to the clutch packs full time, the plates are now burned out rendering the Haldex useless. He thinks it has to do with different brands of tires (no mention of size), I think he's being naive about it.

http://forums.vwvortex.com/showthread.php?6132138-Your-Haldex-Works-Powertrak-Insert-Review

He did not buy the insert, he did some mechanical modification himself.

 

[FPatterson]

hey im know im late to this thread, but i dont plan on doing the mechanical modifications by myself so can someone point me to a link where i can purchase the insert? i trust you guys to point me in the right direction versus myself lol