Has anyone tried or used Haldex Spring Upgrade?

[Gspec76]

As the title states. I have just replaced my pump on my 15 Stage 2 S3, as service. Car has 67k on it. When I launch I still get a lot of front wheel spin. Obviously is much better than when the pump was bad as it was straight FWD, however I was expecting better. I have been researching rebuilding diff with new bearings and seals and Haldex Clutch discs, looked at maybe buying a used Rs3 diff/Haldex, Haldex controller/software upgrade. But I have seen this spring upgrade and cost is low enough to try so wanted to know if anyone has any experience with it. It's $59 I know Iroz includes a spring with their Cyvex Controller kit.

https://tunezilla.com/blog/128/how-t...100-1684883494

The Haldex unit builds clamping pressure on the clutches to engage the rear axles. These parameters are set by the factory and can be adjusted/tuned using software and/or a controller. We wanted to try skinning that cat another way. Inside the Haldex is a pressure relief valve. It's like a diverter valve for your rear differential. Once the pressure of the fluid inside the Haldex unit reaches a certain point, the pressure relief valve opens and allows any additional pressure to flow through. By replacing this spring with a stiffer one, we can mechanically increase the clamping pressure of the Haldex clutches.

Introducing the TuneZilla Haldex Spring Upgrade - And before you ask, no we couldn't think of a better name than that.

IMG_6581.jpg
But how does this improve my quarter mile time?!

By increasing the maximum pressure in the Haldex unit, we are effectively adding more rear wheel torque through the drivetrain. Since the 4 Motion system is FWD biased, the system is designed to allow some rear axle slippage to control wheel spin. With the upgraded spring, during a launch your Haldex is now creating more clamping pressure on the rear differential clutch pack extending that power through the rear wheels instead of allowing the clutches to slip (to reduce wheel spin). This simple upgrade means that you can get a similar effect on your launch as you do with a more expensive (like... WAY more expensive) Haldex controller which are designed to help give a true 50/50 torque split.

Throughout our testing, we saw an average of 1/10 (0.100) of a second shaved from our 60ft times. And if you're chasing that Personal Best, or you're just that little bit away from beating your opponent, that extra .100 could be the difference between winning or losing. The Haldex Spring Upgrade installs in less than an hour and doesn't require any software tuning. However, you do need to reset your Haldex adaptations using VCDS (or similar)

haldex-spring-comparison-dragy.png
At just $60 USD, it's one of the cheapest upgrades that you can do to improve your drag times regardless of your hardware or software upgrades.

Check out the TuneZilla Haldex Spring Upgrade

This spring upgrade is for Gen 5 Haldex

[MikTip]

Here's Hank Iroz word:



https://irozmotorsport.com/

[Gspec76]

Thank you for the reply. I was looking into doing the UM Haldex tune flash as I wanted it to work without changing modes, but I want to know if anyone has ever tried this upgraded spring either without Haldex tune or controller or with a haldex tune flash.

[Gspec76]

Honestly if I knew for sure this would solve my ossue I wouldnt hesitate at spendiong the $1,350 for the IROZ Syvecs controller kit, however I am concerned do I need new or something else. I feel that the bearings should be replaced. I can buy an RS3 rear dif and haldex for 2200. So I'm trying to be careful as to which wat i go for what it needs as I dont want to end up buying expensive parts and ten at the end of the day its still an issue. I wanted to take the car to IROZ since its 10 miles from my house as they are def experts but they do not accept any outside work.

[MESOGLEA]

Here's an interesting video about the Haldex learning procedure with a shimmed relief spring:

https://www.youtube.com/watch?v=ldzk...utoFaultFinder

Using VDCS, a pressure sensor, an ammeter and an o-scope, the learning procedure was performed on a Gen 5. An OEM spring and a shimmed OEM spring were tested back to back.
However, it appears he is using the Van der Veer aftermarket piggyback controller with an unknown map. I don't know if the VdV unit can overdrive the pump or override the standard Haldex module calibration like the Syvecs.

Based on the measured value between the two, a TuneZilla setup should add some rear bias.