# Adjustable OEM Rear Swaybar



## CollecTTor (Jan 17, 2014)

In an effort to change the status quo mindset on swaybars, here's an easy way to upgrade without going aftermarket. I've had aftermarket bars before, and while it's fun to flick the car into a turn and countersteer out from the tripod oversteer, tripod = loss of 1/4 of your traction surface and *less handling capability*, aka BAD. This was my car with a 21mm Neuspeed rear swaybar:










So last night I installed my newly converted to adjustable OEM rear swaybar, ala MadMax's arsenal of tricks. A 3/8th's drill bit works perfect for this. In my collection, I had a spare rear sway that I drilled and painted the night before. Upon removal of the original sway on my daily driver, I'd never seen a rear sway with this style of end. All the other's I've seen had the style on the left. The more spade like shape of the bar on the right wouldn't allow you to move the hole as much due to not having enough flat area for the endlink nut to sit flush, but still could be modified. Both bars measured out at 14mm. I wasn't expecting much of a change due to already having Bilstein PSS coils, but I could tell a difference just going down the incline of my driveway into the street. It's the same feeling as an aftermarket sway, just less of it and free!  Unfortunately, my morning commute is mostly interstate and almost all straight, but my return commmute has a 270* offramp that I take aggressively every chance I get, so I'll report back this evening with more impressions. I'm running on both the inner holes (stiffest setting), but may change one side to the outer hole to have a "middle" setting (compared to both ends being on the outer holes, the "softest" setting) depending on how I like the car's new handling balance. :beer:










Enjoy. 8)


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## Madmax199 (Jun 14, 2015)

Good post Adam! Subscribed to hear your follow up after more driving (and the comments ). Good free mod that has served me well. When I head to the track I also bring a spare 15mm with the extra holes with me. If the track has low to moderate grip, or it's cold or wet, I keep the 14mm that is default on the car -- If it's super grippy (concrete or fresh asphalt without too much sealant), I swap the 15mm to keep roll in check (a bit compromising to overall grip, but helps driver confidence and allow me to stay at 10/10th). If you have a 14mm and a 15mm with the extra holes, you are pretty much covered and can fine tune for any possible track conditions you will find.


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## Gonzalo1495 (Oct 13, 2014)

Good luck with this. Me and Max tried a few months back to change the norm on this over here. People for some reason believe just because there are companies making these 21mm, 25mm bars that they are upgrades... :-|

I personally went with the 15mm R32 US Spec rear bar, when Max crunched the numbers I believe, it was only slightly less than the adjusted OEM 14mm bar. Hopefully you installed some new bushings or poly bushes too while you were at it!
Great job


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## CollecTTor (Jan 17, 2014)

Gonzalo1495 said:


> Good luck with this. Me and Max tried a few months back to change the norm on this over here. People for some reason believe just because there are companies making these 21mm, 25mm bars that they are upgrades... :-|
> 
> I personally went with the 15mm R32 US Spec rear bar, when Max crunched the numbers I believe, it was only slightly less than the adjusted OEM 14mm bar. Hopefully you installed some new bushings or poly bushes too while you were at it!
> Great job


Yeah, I'm too cheap to spend $50-100 on the R32 bar. I'd rather put that money towards Swift springs with increased rates over the standard Bilstein springs. I had the 21mm bar because I bought it when I first got my 180Q knowing that there would be no coilover money for a long time. I still have the bar, but no one will buy it on Vortex. :lol:


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## jamman (May 6, 2002)

Gonzalo1495 said:


> Good luck with this. Me and Max tried a few months back to change the norm on this over here. People for some reason believe just because there are companies making these 21mm, 25mm bars that they are upgrades... :-|
> 
> I personally went with the 15mm R32 US Spec rear bar, when Max crunched the numbers I believe, it was only slightly less than the adjusted OEM 14mm bar. Hopefully you installed some new bushings or poly bushes too while you were at it!
> Great job


Trust me Gonzy we listen to the peeps that have actually done it :wink:

I don't remember anyone doubting Max


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## Gonzalo1495 (Oct 13, 2014)

jamman said:


> Gonzalo1495 said:
> 
> 
> > Good luck with this. Me and Max tried a few months back to change the norm on this over here. People for some reason believe just because there are companies making these 21mm, 25mm bars that they are upgrades... :-|
> ...


The only reason I even commented was because I specifically REMEMBER people doubting the idea.

One of the exact posts almost to the letter was something like "well if thicker is worse, why do so many companies make them" even after the data had been posted.
Not to mention I still see posts on here about people buying 19mm R32 bars or even higher, I gave up on the fight, but I still cringe whenever I scroll past them lol.

Also that makes no sense bud, considering at the time I had already picked up the R32 bar :-* :roll:


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## CollecTTor (Jan 17, 2014)

No interest in free suspension mods?


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## Madmax199 (Jun 14, 2015)

CollecTTor said:


> No interest in free suspension mods?


You're firing blanks buddy... nobody's home! [smiley=guitarist.gif]


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## Gonzalo1495 (Oct 13, 2014)

Drilling holes in my oem bar? Naw, I'd rather shell out $150 for a 21mm bar, and then another $100 for someone else to install it for me. 
^ The mentality here honestly lol


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## Delta4 (Jun 19, 2015)

The arb on my TT is the same as the one on the right in the pic, there is no room for a extra hole to be added so it's a no go for me.


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## NickG (Aug 15, 2013)

My track project is sticking with stock ARB's and we are controlling body roll with the use of far stiffer spring rates (Not off the shelf rates). It's not news that smaller ARB's are favorable with this sort of set-up, however with standard suspension setups and probably to some extent even standard coilovers (Where spring rates are still pretty low) a bigger/stiffer rear ARB will help with the feel of the car, no-one likes body roll hence why on the track we try and control this with spring rates where possible. On the road, where its mainly about feel however, a bigger ARB will help combat body roll, keeping the ride manageable but feeling less sloppy and for a much lower cost.

Horses for courses, just please remember not everyone uses their car for the track so not everything is as suitable for the road!!!

CollecTTor, i however do like the idea and appreciate the thread, it's something i'll look at when i'm next under the car, as it could be useful to change on track if for example it rains (Along with the adjustable damping settings on the coilovers). Nice One


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## Madmax199 (Jun 14, 2015)

NickG said:


> My track project is sticking with stock ARB's and we are controlling body roll with the use of far stiffer spring rates (Not off the shelf rates). It's not news that smaller ARB's are favorable with this sort of set-up, however with standard suspension setups and probably to some extent even standard coilovers (Where spring rates are still pretty low) a bigger/stiffer rear ARB will help with the feel of the car, no-one likes body roll hence why on the track we try and control this with spring rates where possible. On the road, where its mainly about feel however, a bigger ARB will help combat body roll, keeping the ride manageable but feeling less sloppy and for a much lower cost.
> 
> Horses for courses, just please remember not everyone uses their car for the track so not everything is as suitable for the road!!!


Nick, drilling the holes inboard does exactly what a stiffer/larger bar does! So, if anything this mod should appeal to the standard setups with soft springs rates that are looking to limit body roll. Your point is eluding me... as this essentially turns a stock bar into a bigger one on the fly.


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## NickG (Aug 15, 2013)

Up to the equivalent of a 21mm rear bar? Got info to back that up as i find that difficult to believe if i'm honest.


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## Mr_Smith (Jul 24, 2014)

So you just drill a hole closer in? I'm always up for trying something out, especially a free mod!


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## Madmax199 (Jun 14, 2015)

NickG said:


> Up to the equivalent of a 21mm rear bar? Got info to back that up as i find that difficult to believe if i'm honest.


It makes a dramatic difference! The mod is no different than switching holes in an aftermarket adjustable bar, each holes towards the center of the bar increases the effective stiffeness by a substantial percentage. Drilling the hole 1/2" inboard is responsible for a 10% increase in stiffeness. When I do mine, the distance is a little over 1 inch and I get a 20+% increase in effectiveness (which is huge in terms of feel). Give me the diamter (in mm) of the two bar that you want to compare and I'll model both for you!


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## Madmax199 (Jun 14, 2015)

Mr_Smith said:


> So you just drill a hole closer in? I'm always up for trying something out, especially a free mod!


Yes Sir! nothing more, nothing less... and don't froget to bolt the end links in the newly drilled holes. Lol


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## CollecTTor (Jan 17, 2014)

Mr_Smith said:


> So you just drill a hole closer in? I'm always up for trying something out, especially a free mod!


Correct. http://store.uucmotorwerks.com/articles/swaybar_setup.htm I didn't want to comment on the results without more seat time, but the car definitely didn't understeer as badly yesterday in my 270* off ramp that I take daily.


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## CollecTTor (Jan 17, 2014)

Madmax199 said:


> Mr_Smith said:
> 
> 
> > So you just drill a hole closer in? I'm always up for trying something out, especially a free mod!
> ...


Yeah, the weight savings from the two holes alone doesn't really help the handling. :lol:


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## NickG (Aug 15, 2013)

The standard bar (Is it 14 or 15mm) on its stiffest setting if you drill the holes as said compared to a 21mm Neuspeed/Eibach/ST job on it's stiffest setting.

Like i say, i'm going to see if drilling is possible on mine, as it'd be great to have the adjustable factor on track.


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## Gonzalo1495 (Oct 13, 2014)

NickG said:


> The standard bar (Is it 14 or 15mm) on its stiffest setting if you drill the holes as said compared to a 21mm Neuspeed/Eibach/ST job on it's stiffest setting.
> 
> Like i say, i'm going to see if drilling is possible on mine, as it'd be great to have the adjustable factor on track.


The adjust-ability factor alone should merit doing this mod. :roll: It's free lol...

You could do this to bigger bars as well too if you've already upgraded the oem bar.

The stock bar is 14mm, when crunching the numbers, a modified OEM bar behaves slightly stiffer than a US R32 Rear ARB (15mm). At least that is what Max's numbers showed a long time ago when I asked him to crunch them.

viewtopic.php?f=2&t=1062673&hilit=mapping&start=45


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## Madmax199 (Jun 14, 2015)

Here are some actual numbers. I even went under the car to double check the measurements I had saved in my suspension calculator for the TT.

Stock 14mm bar:
158 lbs/in Static rate
133 lbs/in dynamic rate (the dynamic rate is with body roll and the effective rate)

















Modified 14mm bar (1" spacing between bolt holes):
268 lbs/in Static rate
226 lbs/in dynamic rate ===> a 70% increase in effective rate

















19mm Euro-spec R32 bar (seems to be a poular upgrade in the UK):
537 lbs/in static rate
454 lbs/in dynamic rate

















19mm Modified Euro-spec R32 bar:
910 lbs/in static rate 
769 lbs/in dynamic rate ====> a 69.4 increase in effective rate

















For comparison's sake, a 21mm bar with stock-location bolt hole:
802 lbs/in static rate
678 lbs/in dynamic rate ====> this bar is softer in effective rate than a modified R32 bar

















What's my conclusion? IMO, the mod is a very simple way to increase a bar's effective rate without changing it or moving to the next size up, and it gives adjustability. By moving

A stock 14mm rear bar will see a 70% increase in stiffeness which is substantial. The 19mm Euro-spec bar that is a common mod here will be stiffer than a 21mm aftermarket bar at its center hole.

For those that might care about that kind of stuff (doubt there are many in the audience). A 21mm bar is a staggering 409% increase over the standard 14mm bar -- therefore even more if going with bigger than 21 mm. With increase that excessive, the bar is basically doing all the work (might as well run on bar only). All independence is out of the window, and while a car like that may feel flat while due to the lack of body roll, it is obviously not going to actually handle better than a car where the spring is the main player and the bar is complementary.

I'm not going to tell people what they should run (to each their own), but wanted to put the data out there. Use it for what it is... cheers!


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## NickG (Aug 15, 2013)

Extremely interesting info Max, props for compiling that!

For the average person then, it could be said that a 19mm ARB on standard holing could be a nice upgrade for those with daily drivers? For not too much money!

I love the info on the 14mm bar though, I run 16mm stock bar so somewhere between 133 and the 19mm 454 dynamic then, I'm sure it's worth a go drilling it for the firmer setting to run on a dry track and adjust my dampening to work with this. Then if it goes wet on track it's a quick swap to move the ARB back to original holes and instantly give a bit of independence back?


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## Madmax199 (Jun 14, 2015)

NickG said:


> Extremely interesting info Max, props for compiling that!
> 
> For the average person then, it could be said that a 19mm ARB on standard holing could be a nice upgrade for those with daily drivers? For not too much money!
> 
> I love the info on the 14mm bar though, I run 16mm stock bar so somewhere between 133 and the 19mm 454 dynamic then, I'm sure it's worth a go drilling it for the firmer setting to run on a dry track and adjust my dampening to work with this. Then if it goes wet on track it's a quick swap to move the ARB back to original holes and instantly give a bit of independence back?


I'm glad you find it useful!

Your 16mm bar has the following data:
270 lbs/in static rate
228 lbs/in dynamic rate ===> the effective rate on this bar is basically identical to a standard 14mm bar with the drilled mod

















If you were to mod your 16mm bar, this what you'd have at a 69.2% increase :
457 lbs/in static rate
386 lbs/in dynamic rate ===> which is not far trailing an unmodified 19mm bar from an R32
















As for daily drivers on standard shocks/springs or aftermarket shocks/lowering springs, I would say that the 19 mm R32 bar is a nice cheap "upgrade", but honestly at the borderline of practicality where you're hurting more than you're helping. If on coilovers with more decent spring rates, I think that something like your 16mm bar is as far as I would push it... but I'm sure others have their own differing opinion based on whatever testing they have done.


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## NickG (Aug 15, 2013)

Thanks again Max, appreciate the info on my 16mm bar!

Also agree with your statement regarding dailys and ARB selection.


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## hang your idols (Jul 8, 2013)

I have 22mm in the front and 19mm in the rear with H&R springs with new OEM shock absorbers and 15mm wheel spacers front with 20mm rear;for a daily driver it`s very nice,night and day difference.
Sometimes i like to play with my car pushing hard in the corners and...there is a bit of understeer,it`s not very well balanced,but it`s easy to control it.


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## Madmax199 (Jun 14, 2015)

hang your idols said:


> I have 22mm in the front and 19mm in the rear with H&R springs with new OEM shock absorbers and 15mm wheel spacers front with 20mm rear;for a daily driver it`s very nice,night and day difference.
> Sometimes i like to play with my car pushing hard in the corners and...there is a bit of understeer,it`s not very well balanced,but it`s easy to control it.


Isn't the stock ARB 20mm in the UK? The 22mm bar is what making the car still prone to understeer (when you have a 19mm rear bar). I bet if you go back to a 20mm bar (if that's what was standard in the car), you'll have a much more favorable balance with the rear breaking loose before the front. :wink:


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## L0wer (Jul 26, 2015)

be rude not to do this while i'm under the old girl next week :mrgreen: .
best order some poly bushes  
thanks for the info
Brad


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## hang your idols (Jul 8, 2013)

Madmax199 said:


> hang your idols said:
> 
> 
> > I have 22mm in the front and 19mm in the rear with H&R springs with new OEM shock absorbers and 15mm wheel spacers front with 20mm rear;for a daily driver it`s very nice,night and day difference.
> ...


It`s H&R 22mm front ARB and yes,stock was 20mm.

At the begging i changed only the rear ARB,but somehow,i don`t know how to explain,in the corners the front of the car was weak,like the rear was pushing the front(i`m not the only one which reported this).

Now,even with a bit of understeer it`s better,so i prefer this set up;maybe it`s better with 21mm front and 19mm rear?,i don`t know,i will leave it like this,my money it`s going to the engine:big turbo,etc


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## longodds (May 8, 2014)

Can someone advise, practicalities aside, if the drop link mounting holes were moved significantly further back, could that cause the bar to snap? If it could, what might be a safe maximum distance to move the hole from its stock position?


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## CollecTTor (Jan 17, 2014)

longodds said:


> Can someone advise, practicalities aside, if the drop link mounting holes were moved significantly further back, could that cause the bar to snap? If it could, what might be a safe maximum distance to move the hole from its stock position?


Unless you had significant rust, why would it break? It's not hollow like some of the Neuspeed bars have failed. Mine's been fine for over a year since this post was made.


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## Madmax199 (Jun 14, 2015)

CollecTTor said:


> longodds said:
> 
> 
> > Can someone advise, practicalities aside, if the drop link mounting holes were moved significantly further back, could that cause the bar to snap? If it could, what might be a safe maximum distance to move the hole from its stock position?
> ...


I have been rocking this mod since 2012 with daily and track use. If there was a way to break anything, I think I would have done it by now.


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## longodds (May 8, 2014)

If you've read this excellent post you'll be aware that moving the drop link to (rear) ARB connecting point further towards the rear of the car increases the effective stiffness of the ARB. As the post correctly states, a second hole can be drilled in an existing or standard ARB to achieve this, but some ARB's don't have space to allow that and when they do there is a limit to the distance from the existing mounting hole that you can drill a second hole to accommodate the drop link.

So, I've taken the fundamental idea a step further by designing and developing an intermediary part that connects the drop links to the ARB in such a manner that allows the drop link to be connected to it at its standard position or as far back as 70mm (2.75"). Thus stiffening the rear suspension and dialing out under steer.

The part removes the need to drill any holes in the ARB, it provides an infinitely adjustable drop link connecting point (from 0.0mm to -75mm) to aid tuning and its left and right side parts can both be fitted by most owners in approximately 30 minutes, plus the modification is completely reversible.

I've been testing the prototypes I've had made for a few months now on my own TT but as I'm limited to public roads and don't tend to throw the car about much I've been unable to test them to the limit to fully ascertain how effective they are in tuning the handling.

Hence this addition to the post; would any of you track guys be prepared to fit them to your TT, road test them and provide an assessment and review in return for a production sample of the finished product?

Hoping someone can help.


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## NickG (Aug 15, 2013)

longodds said:


> If you've read this excellent post you'll be aware that moving the drop link to (rear) ARB connecting point further towards the rear of the car increases the effective stiffness of the ARB. As the post correctly states, a second hole can be drilled in an existing or standard ARB to achieve this, but some ARB's don't have space to allow that and when they do there is a limit to the distance from the existing mounting hole that you can drill a second hole to accommodate the drop link.
> 
> So, I've taken the fundamental idea a step further by designing and developing an intermediary part that connects the drop links to the ARB in such a manner that allows the drop link to be connected to it at its standard position or as far back as 70mm (2.75"). Thus stiffening the rear suspension and dialing out under steer.
> 
> ...


Got any pics? Happy to throw a set on and blast them if you don't get any other takers!


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## longodds (May 8, 2014)

NickG said:


> longodds said:
> 
> 
> > If you've read this excellent post you'll be aware that moving the drop link to (rear) ARB connecting point further towards the rear of the car increases the effective stiffness of the ARB. As the post correctly states, a second hole can be drilled in an existing or standard ARB to achieve this, but some ARB's don't have space to allow that and when they do there is a limit to the distance from the existing mounting hole that you can drill a second hole to accommodate the drop link.
> ...


Pictures in the forum marketplace headed ARB Tuners. I'd welcome members thoughts on them.


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## A_Banging_Donk (Apr 22, 2017)

longodds said:


> Pictures in the forum marketplace headed ARB Tuners. I'd welcome members thoughts on them.


These look well smart, if I wasn't so happy with my current setup, I'd buy in a heartbeat


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## Hoggy (May 8, 2002)

Hi, It appears lots thought went into them, so look simple but effective. [smiley=thumbsup.gif] 
Hoggy.


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## Madmax199 (Jun 14, 2015)

Pretty cool idea - Well done!


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## longodds (May 8, 2014)

Thank you all for the positive remarks.


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## Delta4 (Jun 19, 2015)

Nicely made bit of kit and a very good price when you consider the price of a replace rear ARB.


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## David C (Apr 15, 2013)

They looks very nicely done.

Only think I'd say is to label them "Left" & "Right" (which the same everywhere) instead of "Nearside Passenger Side" & "Offside Drivers Side".


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## longodds (May 8, 2014)

David C said:


> They looks very nicely done.
> 
> Only think I'd say is to label them "Left" & "Right" (which the same everywhere) instead of "Nearside Passenger Side" & "Offside Drivers Side".


Very good point. Thanks.


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## longodds (May 8, 2014)

I'd like considered advice regarding the following. In my advert for these components I've included a disclaimer to the effect that although they can be used on road going vehicles I'm only recommending them for track use. Basically to try and cover my butt.

I've been running them on my car for about nine months now with good results and no ill effects. Given that they do nothing more than provide similar results to fitting a bigger ARB do you think I'm being over cautious by including the disclaimer?


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## longodds (May 8, 2014)

Come on guys, I need advice and every members opinion is valid.


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## David C (Apr 15, 2013)

longodds said:


> Come on guys, I need advice and every members opinion is valid.


Given the world we now live in, I think you are wise to recommend track use only.


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## Hoggy (May 8, 2002)

Hi, "Any suspension modifications are at your own risk" would cover everything.
Hoggy.


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## longodds (May 8, 2014)

Hoggy said:


> Hi, "Any suspension modifications are at your own risk" would cover everything.
> Hoggy.


Well stated Hoggy. Thanks.


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## NtG (Jan 2, 2018)

CollecTTor said:


> I wasn't expecting much of a change due to already having *Bilstein PSS coils, *but I could tell a difference just going down the incline of my driveway into the street.


Forgine my ignorance, what's the "special" with the Bilstein PSS and you were not expecting much of a change?


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