Definitive VAQ and XDS Settings in OBDEleven / VCDS

[mrd8cd]

After a ton of searching and reading on the forums, I couldn't find definitive answers to what our VAQ and XDS settings should be for optimum traction and handling. There are so many conflicting answers out there that it's nearly impossible to determine the "right" answer.

A little backstory: when I initially test drove the GTI before buying it, there was a stretch of road on the test drive that was a nice banked 90 degree turn that had a recommended speed of 20 mph. As I approached the turn, the salesman said "downshift into 2nd and floor it through the turn." I remember thinking "you want me to what??" Anyway, I did as instructed and I was almost sure we were going to understeer through the turn and right off the road. Sure enough, we did not, and I could feel the car pulling the outside front of the car through the turn like it was some kind of magic. I was seriously impressed at how a FWD car could take a turn like that and feel almost like a RWD car. I ended up buying a sport trim (the test drive car was an SE), and ever since then, I haven't been able to replicate the feeling of being pulled through turns like that.

So the question I pose to you all is what do our XDS and VAQ settings need to be in order to achieve the best possible handling through turns? Some might call it a feeling that the car is on rails. For reference I have a 2017 GTI sport 6MT with a 24mm H&R sway bar and Michelin Pilot Sport All Season 4 tires (not summer tires, but arguably the best all seasons you can buy and definitely better than the Hankooks on the test drive car). Any helpful input would be greatly appreciated!

 

[Reggie Enchilada]

Do you have the VAQ diff? It would be standard on the performance pack option.

 

[mrd8cd]

Do you have the VAQ diff? It would be standard on the performance pack option.

Yes, I do. I thought about mentioning that after I created the post, but I thought it would go without saying since I put VAQ in the title and mentioned that I have a sport trim, which came with the lighting and performance packs.

 

[GTIfan99]

Most feel VAQ set to increased traction and xds on weak is the best. I don't think anyone has done timed back to back tests.

 

[mrd8cd]

Most feel VAQ set to increased traction and xds on weak is the best. I don't think anyone has done timed back to back tests.

Thanks sir! I'll try out those settings this weekend.

 

[ucfquattroguy]

About the XDS "weak" setting: Considering the VAQ unit itself has no static preload, you may find the engagement of the VAQ a bit On/Off or jerky during faster cornering. Actuating the inside-front brake a tiny bit at the initial onset of wheel slip smooths out the engagement of the VAQ.

Set it how you want. Driver preference really. I have my VAQ set to "Increased Traction", but have left the XDS alone. Zero complaints. Engagement is super smooth and fairly transparent. The two systems really are designed to work together.

 

[tigeo]

Because nobody has shown definitively what these settings do - it's all based on speculation and feel which is v. subjective. Somebody at some point looked around with the VCDS/OBDEleven stuff and saw these settings and assumed what they did...

 

[GTIfan99]

Because nobody has shown definitively what these settings do - it's all based on speculation and feel which is v. subjective. Somebody at some point looked around with the VCDS/OBDEleven stuff and saw these settings and assumed what they did...

IIRC, the CS and CSS come with VAQ set to increased traction, so I think that's a no brainer. XDS is all going to come down to driver preference.

The choice is easier on non PP cars without VAQ. My 2018 would overheat the brakes to the point of melting the center caps with xds on and no VAQ. Car was faster and brakes and tires didn't melt off the car by the third lap.

 

[mrd8cd]

Thanks for the input guys. Does anyone know where the "increased traction" setting is in OBDEleven?

 

[GTIfan99]

Lock Electronics 32>Adaption>Acoustic Measure, Wiring Logic>increased traction

 

[seanmcd1]

Borrow someone's old 90's Honda and drive it for the weekend. Then get back into your car. You'll realize you don't need to do anything.

 

[Hollywood0220]

The settings are best when the sensors signal that one of the front wheels is moving at a different rate that the other. The further this dynamic is apparent (applied) the more the VAQ will apply. Traction is also dependant of the tires and the characteristics of the suspension.
Control this by modulating the throttle. Also ensure that your own limits are not exceeded - as any car will lose control in speeds in excess of the laws of gravity.

 

[shovelhd]

Because nobody has shown definitively what these settings do - it's all based on speculation and feel which is v. subjective. Somebody at some point looked around with the VCDS/OBDEleven stuff and saw these settings and assumed what they did...

I know you like to be the settings fact checker here, but empirical data has value. Even a scientist will tell you that. Everything doesn't need a double blind independent study to show effectiveness.

I have a "T" intersection on my way to work. I take a left, up a hill, and the turn is off camber. Before I changed the VAQ value, I'd get wheelspin with anything more than light throttle. Now I only get it with full throttle. Same car, same tires (good ones), same temperature, same tune settings, same road conditions.

 

[tigeo]

I know you like to be the settings fact checker here, but empirical data has value. Even a scientist will tell you that. Everything doesn't need a double blind independent study to show effectiveness.

I have a "T" intersection on my way to work. I take a left, up a hill, and the turn is off camber. Before I changed the VAQ value, I'd get wheelspin with anything more than light throttle. Now I only get it with full throttle. Same car, same tires (good ones), same temperature, same tune settings, same road conditions.

Subjective data does have value, it's what drives the desire to scientifically test things. You make a change and you feel a difference. Great. You have a perfect set up on that road section for a test. We have a tool that allows all of these changes but few want to use it to test what they do which should be simple. I'm sure in the live data or charts (OBDEleven) under that control unit there is a way to log the activity of the VAQ just like you can log the activity of the Haldex on the 4Motion vehicles. Should be easy to do this drive twice one with each setting, maintain to the extent possible the same acceleration/speed/etc. and log it and see what is going on and compare them. I'm not a fact checker or double-blind test Nazi, I just find all of this interesting and want to remove the subjective/butt-dyno/placebo stuff if possible b/c it's very real with car mods/upgrades is all. I'm a science guy buy profession (geologist....if you think that's a real science..hahahaha) and just like to see more concrete data is all. You read about these changes (take the Haldex "increased traction" mod for example) and have a huge span of what folks think they feel that it does from nothing to "full time 4wd bro" - that's what should drive asking good questions about what these changes are actually doing, if anything. Log it and I see no difference. That's really all it is for me.

 

[shovelhd]

Well that makes perfect sense to me. I'm willing to test. I have a VCDS cable, not OBD11. I don't know how to set up VAQ logging. If you can help with that, I'll do the test, and we'll see what happens.