Did not like a thicker sway bar

[EricsVdub]

Big picture, dude, that’s what springs do, resist being compressed.

Ugh, somebody fucked up on that article. Take it to the logical extreme - stupid stiff, nigh infinite spring rate springs. In other words, a big block of steel. Is the car going to roll more or less than with soft springs?

You can also run it with more real numbers. Say you have a 250lb rate spring and 500lbs on each corner. Normal compression is therefore 2" on each side.

A turn moves 75% of that weight onto the outside wheels. You now have 750lbs on each outside wheel, and 250lbs on the inside. That means 3" compression on the outside and 1" on the inside, a difference of 2".

Now let's run it with 500lb springs. Now we have 1" of compression on each side when flat. Same turn, same weigh transfer (note: springs cannot affect weight transfer besides geometry changes from lowering!). Outside spring now compresses 1.5", inside spring only 0.5". A difference of 1".

You can see the relationship clearly - a stiffer spring will control roll in proportion to its spring rate.

Now, there are downsides to stiffer springs too - on a rough surface, you have less compliance, which means less traction. Not to mention ride comfort.

Also note that body roll is not necessarily bad, except as it relates to geometry changes in the suspension (something macpherson struts don't do great at). It might feel bad, but it's too often seen as the problem rather than a symptom.

We'll have to agree to disagree. Others can decide for themselves.

 

[mac340]

sorry dont mean to hijack this thread, I'm about to pull the trigger on a 24/25mm rear swaybar.
I have all stock suspension other than Michelins PS4Ss, and the car is aligned right when new tires are on.

Will I have any issue? Do I need new endlinks?

Thanks!

I have stock suspension and PS4Ss, I put on an Eibach RSB and notice minimal difference. Though I do have the experience package which has the 21.7mm RSB instead of the 20mm so maybe that's why i don't notice as much difference.

 

[xXDavidCXx]

We'll have to agree to disagree. Others can decide for themselves.

This paragraph from your link is garbage:

"Let’s discuss roll control provided by springs. For “linear rate springs” the discussion is easy. They provide no roll control! Think about taking curve at a very high speed. The side of the car on the outside of the turn rolls over and the side of the car on the inside tends to roll up. For discussion sake, let’s assume we have 300lb/in linear rate springs on the front of our car and the car is rolling too much and cornering speed suffers. If we move up to a set of 400lb/in springs in an attempt to “stiffen” the suspension, we fail because the linear rate springs provide no roll control. Think about it. As you enter the same curve at the same speed your vehicle is rolling onto a higher rate spring; BUT the inside of the vehicle is being pushed up by a higher rate spring, also. So there is not improvement with roll control. With linear rate springs, all roll control must come from the sway bar (anti-roll bar)."

I just put linear rate springs on my car and I have verifiable data that suggests that the decrease in roll, was due to the spring. No other item that changes overall body roll degree was changed.

Even though there is some truth to the inside spring pushing up "some" it's not pushing the car all the way to the other side.

The outside spring "has" to resist compression, otherwise the car would flop over and crush the spring and bottom out.

The paragraph above is a gross over-simplification using a very narrow definition without using any concrete data of roll angle, roll center or any other objective measurement of roll.

 

[jimlloyd40]

I have stock suspension and PS4Ss, I put on an Eibach RSB and notice minimal difference. Though I do have the experience package which has the 21.7mm RSB instead of the 20mm so maybe that's why i don't notice as much difference.

Try pushing it harder on a curve and you'll notice a difference.

 

[SouthFL_Mk7.5]

As for feeling more understeer after a RSB install, on post #6 of this thread

https://www.golfmk7.com/forums/inde...he-conservative-approach.371249/#post-7391043

I do report sensing a bit more understeer at initial turn in, but go on to describe how the back end wakes up upon committing to apex and track out with the RSB newly installed.

Months later, I’m still really happy with the overall outcome of the RSB as it relates to the GTI’s dynamics.

 

[FlyingNugget]

Like others have mentioned, start with checking alignment.

When I was reading through many autocross threads on STH class setup, there were some complaints about understeer at certain points in the turn with a bar too stiff - usually initial turn in.

Personally, I think the H&R 26mm is VERY aggressive for a daily driver/non autocross setup. I run the H&R 24mm, but I also have camber plates, track alignment, and re71r tires. If you hammer the gas mid turn, it's going to push on a FWD car - you can't just slap on a massive RSB and drive it like a RWD car.

 

[Gvazquez]

As for feeling more understeer after a RSB install, on post #6 of this thread

https://www.golfmk7.com/forums/inde...he-conservative-approach.371249/#post-7391043

I do report sensing a bit more understeer at initial turn in, but go on to describe how the back end wakes up upon committing to apex and track out with the RSB newly installed.

Months later, I’m still really happy with the overall outcome of the RSB as it relates to the GTI’s dynamics.

I agree with this. I notice a slight dead spot in steering especially in transitions but when you commit to the direction you want to be in, its very eager to rotate

 

[art_mark7]

I have stock suspension and PS4Ss, I put on an Eibach RSB and notice minimal difference. Though I do have the experience package which has the 21.7mm RSB instead of the 20mm so maybe that's why i don't notice as much difference.

Did you mean performance package? I have it too but didnt know our RSB is 21.7 instead of 20 hmm

 

[sloopercat]

With the thicker rear bar, the car will still understeer when pushed hard, just less than before. Hard to get around some understeer with a FWD and relatively heavy car. The VCDS setting, if you have that option, seem to help with the initial turn in lag. It definitely is a big improvement over the OEM set up.

i think the different experience folks are reporting may be due to how hard they push the car and possibly their experience levels. Of course different set ups are always the way it goes. What feels good and balanced for me may seem wildly out of whack for someone else, or at least not ideal. Driving style plays a huge role. Throw in tires and alignment and .........., it becomes harder to compare what happens when only the rear bar is considered.

 

[mac340]

Did you mean performance package? I have it too but didnt know our RSB is 21.7 instead of 20 hmm

No, from what I have seen (and after a fair amount of research) the Experience package on the SE and also the Autobahn version has the 21.7 mm RSB.

 

[Deanjet]

Also I installed it on jack stands but I was just reading some post and people are saying it should be on the ground?

I have done it both ways. Same results. The absolutr best way is on the ground (i.e. ramp the rear) and use adjustable end links so there is zero pre-load on the bar. Them torque to specs.

 

[sloopercat]

The endlinks have a spherical ball joint so where they are installed should make no difference to the function. Setting the adjustable links at ride height is the way to go.

 

[aroundomaha]

I installed the H&R 26mm bar last October (stock endlinks). When I run the stock tires (Potenza RE97AS) I get different results than when I mount my RE71Rs. The flexible sidewalls and low grip of the RE97AS tires make the RSB difference less pronounced. But when I swap to wheels with RE71Rs on them I can induce oversteer with trail braking.

There is a large, noticeable difference, as in like night and day.

I don't know how you are inducing understeer with the larger sway bar, but like several others think you might need to consider which tires you are on, tire pressures, alignment, etc. That should not be the case.

Even with the crappy RE97AS tires I get more balanced handling than I had with the stock sway bar.

 

[vw1320]

Which vcds setting to reduce the dead spot on center? That is one of my complaints with my car. Might have to try the moog end links as well.

 

[sloopercat]

I don’t have my notes with me, but this is one setting to change. Set it to strong.

XDS
Select Control unit 03 (ABS)
Adaptation
Select: Expanded Electronic Differential Lock
Options: Weak – not active - Standard – Medium - Strong

There are a couple other tweaks, I cannot find them in this or the VWVortex forum at the moment. Finding these performance VCDS tweaks for the 7.5 is a bit like finding a needle in a haystack. They seem to be buried in other posts about sway bars and handling for the most part. If you want to do some trivial light mod, those are easier to find.