GTI Rear Sway Bar

"LimitedTimeOnly @ opposite-lock.com" (limitedtimeonly)
12/09/2017 at 22:09 • Filed to: Sway bars, Autocross

Okay, Oppo, I’m doing the research to get a new rear sway bar (and endlinks) for my 2016 GTI to combat understeer for my autocross outings. It is impossible to compare products because of no standard comparable metric. One product described a “spring rate” in lb/in and compared it to the stock RSB, but no one else does. They don’t even offer product weight, which would seem really basic!

So I am left reading forums on sites like VWVortex for opinions ( !!!error: Indecipherable SUB-paragraph formatting!!! ) and, I guess, taking a guess.

One factor is that I have the “Dynamic Chassis Control” DCC option with the adjustable suspension, so I am not combining this with Koni shocks as the nationally competitive GTIs have done. And another is that I am building for G Street, so I can not (and don’t care to) alter the springs. Finally, the stock bar is a nice 21.7mm hollow bar, so I am looking at 25mm or 26mm options.

Are there GTI owners here who have spent time with this and would care to discuss what I’ve found so far?

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DISCUSSION (19)

sony1492 > LimitedTimeOnly @ opposite-lock.com
12/09/2017 at 22:35

Have you played around with tire pressure?

LimitedTimeOnly @ opposite-lock.com > sony1492
12/09/2017 at 22:39

I have a lengthy post that I avoiding making, which answered that: Yes, I ran with higher pressure in the rear, which helped some and was fine for the first year but basically resulted in 4 wheel slides. I’d like to be more controlled, and all my competitors seem clear that a RSB will help with that.

AestheticsInMotion > LimitedTimeOnly @ opposite-lock.com
12/09/2017 at 22:54

Give the various Gti vendors designing these a call. If they’re worth your time, they should be racing using the exact same gear they sell, and have solid data to provide vs stock sways, or even other aftermarket bars.

For something so relatively cheap and easy to swap, I would be very surprised if there isn’t a halfway decent comparison somewhere out there...

(edit) most products will generally have their own thread on “instead Gti forum here”. That’s a good place to start, since you’ll generally see Q&A style discussion between the consumers and the manufacturer/designer. I don’t know anything about the VW community, but I’d assume that a swaybar thread should be full of actual racers who are anywhere from semi-knowledgable, to engineer level

AkursedX > LimitedTimeOnly @ opposite-lock.com
12/09/2017 at 23:06

A friend of mine runs the 26mm h&r rsb on his mk7 w/dcc. He is usually a top-10 pax-overall guy with it. Another friend of mine co-drove it as well and he was right up there in that range too (tires were re-71's of course). I don’t have any input as to the feel of it, but apparently it seems to help!

ADabOfOppo; Gone Plaid (Instructables Can Be Confusable) > LimitedTimeOnly @ opposite-lock.com
12/09/2017 at 23:19

Have a 16 GTI. Can confirm that understeer is a thing that is very real. The performance package diff doesn’t help much either.

I am waiting on APR to finally release their MK7 springs before I look into an RSB. I also don’t Auto-X because I haven’t the time for it. So I just want my car to be more fun as a daily driver.

OmerCarrothers333 > LimitedTimeOnly @ opposite-lock.com
12/09/2017 at 23:29

I’m a MK6 guy, but have you thought about seeing if any of the suspension parts from a newer A3/S3/A4 could work? In theory, it would do the same thing as the aftermarket, but cost less.

SilentButNotReallyDeadly...killed by G/O Media > LimitedTimeOnly @ opposite-lock.com
12/10/2017 at 00:10

Interesting. The Whiteline RSB for the MK7 is a 22 mm...

Nerd-Vol > LimitedTimeOnly @ opposite-lock.com
12/10/2017 at 00:14

Not to get off topic, but perhaps you adjusted the tire pressure in the wrong direction?

https://m.tirerack.com/tires/tiretech/techpage.jsp?techid=58

LimitedTimeOnly @ opposite-lock.com > Nerd-Vol
12/10/2017 at 07:52

I spent a novice school experimenting, as did my competitor with shared notes, and consulted with highly competitive front wheel drive folks. This felt the best to us. I will say that two folks running GTIs in the pro class do the opposite with pressure, so you might be right, but I chalked that up to them using the Konis and stiff RSB, so different set up.

LimitedTimeOnly @ opposite-lock.com > ADabOfOppo; Gone Plaid (Instructables Can Be Confusable)
12/10/2017 at 07:55

The LSD does help, though. I’ve had to relearn how to drive at limit because of what it can do, and previously running rear wheel drive cars at limit.

LimitedTimeOnly @ opposite-lock.com > OmerCarrothers333
12/10/2017 at 07:56

A lot of the RSBs seem to be labeled for use in the A3 also.

LimitedTimeOnly @ opposite-lock.com > SilentButNotReallyDeadly...killed by G/O Media
12/10/2017 at 07:58

There are some aftermarket 22s, which would be a milder upgrade for those GTIs that come stock with the 20mm.

LimitedTimeOnly @ opposite-lock.com > Nerd-Vol
12/10/2017 at 08:38

Looking at the TireRack chart, as you follow down the page it describes adjustments to counter oversteer, and these line up with my approach of high rear tire pressure.

LimitedTimeOnly @ opposite-lock.com > ADabOfOppo; Gone Plaid (Instructables Can Be Confusable)
12/10/2017 at 09:49

I find that as a daily driver it is really well balanced (including making fast left turns to beat lights at bumpy intersections . . . Allegedly). It is only at 10/10ths in autocross or on mountain roads (allegedly) where I find the understeer problematic.

OmerCarrothers333 > LimitedTimeOnly @ opposite-lock.com
12/10/2017 at 15:05

What about the Golf R’s rear sway bar? Could that work?

LimitedTimeOnly @ opposite-lock.com > OmerCarrothers333
12/10/2017 at 15:32

The Golf R rear sway bar is the same one that is on my GTI with the DCC option (21.7mm hollow) as I understand it. And yet it appears to be priced a few bucks higher than the replacement for mine!

The same seems to be the case for the stock A3 RSB. Also seems true for the stock S3 RSB, although it looks a bit different, probably due to Quattro affecting the shape.

So, it doesn’t appear that there is a cheap OEM swap from another car with the same platform. Good idea, though.

Nerd-Vol > LimitedTimeOnly @ opposite-lock.com
12/10/2017 at 23:04

Air pressure is the one place where it seems to run counterintuitive from other suspension settings. On the tire rack chart running a lower rear pressure will reduce understeer. It is a bit of a head scratcher as we think of a lower inflation pressure would make the tire softer and provide more grip, it appears it has the opposite effect.

LimitedTimeOnly @ opposite-lock.com > Nerd-Vol
12/11/2017 at 06:56

Speaking from my experience, it definitely required higher rear pressure to counter the understeer. Much experimenting was involved. But I do see that I didn’t read that chart correctly.

chilichez > LimitedTimeOnly @ opposite-lock.com
12/30/2017 at 18:54

I autocross a 2014 MK6 out here in Colorado, GS. Threw a Hotchkis 27mm rear bar on the car this winter series, set on soft. 18 inch RPF1s, RE71Rs, Koni yellows on half turn from soft, traction control off. Top 10 PAX car instantly with the bar, where I was 20-25 most weeks (normal turnout 125+ in summer) without the bar and with the traction control on.