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piney500
11-17-2014, 12:28 AM
OK, this is a little embarrassing, to say the least, but here goes. So, my 500T is the first car I've owned since my long distant youth that I'm able to tweak and make more sporty. I need to preface this by saying that I'm definitely not the most mechanically inclined person in the world (so brace yourself for stupid question time) and don't even really have a grasp on anything but the basics of maintenance. Good news is I'm a great visual learner and I do have a savant-like ability to "monkey see, monkey do" so at least there's that.

Anyway, to the main point of my post. I've gleaned through reading hundreds of posts over the last few weeks that before I go trying to increase the forward momentum of my car I probably want to stiffen up the suspension. Makes perfect sense to me. I do, however, have questions. Mainly about what impacts the ride and handling the most and where I can get the most immediate benefit for the money, because this will affect the order of priority on my to-do list. Having said that, I'm pretty sure that I'd like to do the following (not listed in any particular order):

Koni rear shocks
Rear Anti-sway/torsion bar (?)
Chassis braces
Front brace bar

Here are my questions:

1. Since I'm just shopping right now, what is the difference between an anti-sway bar and a torsion bar? Is there any difference or are they just two names for the same thing? I know it sounds like a super dumb question, but I certainly don't want to buy the wrong thing.

2. Which of the listed components will give me the most benefit right away without depending on the others, i.e. is the anti-sway bar going to do me much good without the benefit of the Konis?

3. If I have a front brace bar, do I really need chassis braces?

Thanks much in advance for any help and for humoring an idiot. Really appreciate it! :smile:

nilfinite
11-17-2014, 01:01 AM
1. Yup on the rear of the car, torsion bar and sway bar are the same thing.

2. The shocks and sway bar are both independently good. Don't need both if you don't want to spring for both. I'd recommend the shocks and chassis brace first just because they are the easiest. The biggest benefit will come from the torsion bar. For the turbo, I think you have three torsion bar options. The ST & RRM bars which require a hole drilled on each side or CPR's weld-on brackets. I personally like CPR's weld-on because you can pick the thickness of the torsion bar that you put on but that's only if you do plan on racing the car.

3. By the front brace bar, are you referring to the bar in the engine bay or CPR's bar that goes on the bottom of the car? The engine bay bar is useless. CPR's bar is great but independently good, you don't absolutely need both. But having both would help.

piney500
11-17-2014, 01:13 AM
1. Yup on the rear of the car, torsion bar and sway bar are the same thing.

Kind of thought so. Thanks for confirming. I'm assuming that mainly what they do is keep the car from rolling as much?


2. The shocks and sway bar are both independently good. Don't need both if you don't want to spring for both. I'd recommend the shocks and chassis brace first just because they are the easiest. The biggest benefit will come from the torsion bar. For the turbo, I think you have three torsion bar options. The ST & RRM bars which require a hole drilled on each side or CPR's weld-on brackets. I personally like CPR's weld-on because you can pick the thickness of the torsion bar that you put on but that's only if you do plan on racing the car.

Don't plan on racing (at least not for now), just want some increased performance handling. And I do plan on going with CPR's gear. I was also under the impression that lowering the car with the shocks would help the bar do it's job better, so would one not benefit significantly from the other?


3. By the front brace bar, are you referring to the bar in the engine bay or CPR's bar that goes on the bottom of the car? The engine bay bar is useless. CPR's bar is great but independently good, you don't absolutely need both. But having both would help.

As mentioned above, I do plan on using CPR's hardware so it would be the bottom one. Thanks!

opiateESP
11-17-2014, 01:38 AM
1. Yup on the rear of the car, torsion bar and sway bar are the same thing.

2. The shocks and sway bar are both independently good. Don't need both if you don't want to spring for both. I'd recommend the shocks and chassis brace first just because they are the easiest. The biggest benefit will come from the torsion bar. For the turbo, I think you have three torsion bar options. The ST & RRM bars which require a hole drilled on each side or CPR's weld-on brackets. I personally like CPR's weld-on because you can pick the thickness of the torsion bar that you put on but that's only if you do plan on racing the car.

3. By the front brace bar, are you referring to the bar in the engine bay or CPR's bar that goes on the bottom of the car? The engine bay bar is useless. CPR's bar is great but independently good, you don't absolutely need both. But having both would help.

Well said.

Just to add. Mine is lowered on stock shocks and they don't feel as good as they were stock so I suspect there's some premature wear going on. Consider Coilovers or full Koni setup.

streetsurfer
11-17-2014, 01:42 AM
This article on suspension designs may help you with your decisions.

http://www.rqriley.com/suspensn.htm

SeaDawg
11-17-2014, 02:41 AM
I owned a 2012 Sport, which has basically the same suspension as the T, for 2 1/2 years before I purchased the Abarth. If you do buy lowering springs you will find the added stiffness of the springs will virtually eliminate body roll by them selves. But, I personally went with the RRM rear sway bar and I found it helped keep the wheels planted on some washboard pavement not far from my house. If there was any body roll/lean before the addition of the rear sway bar, there wasn't any after the fact. I never upgraded the shocks on that vehicle, but it would probably be worthwhile as the amount of rebound is decreased when you install the lowering springs. I'd also probably recommend NorCalSS's modified bump stops to give you more rear suspension travel room with the lowering springs. I had the chassis braces installed, but never added any additional bars up front.

Good luck with your mods!

MAZ
11-17-2014, 11:37 AM
1. Yup on the rear of the car, torsion bar and sway bar are the same thing.
Umm, Isn't the 'torsion bar' the rear beam that acts as the rear 'axle'? In VW nomenclature it is called the 'torsion beam axle'
(On the 500 it is the part that flips down when you want to remove the spings)
And the rear sway bar is a separate piece all together, it runs parallel to the torsion beam axle to stabilize it?
Perhaps terms 'torsion' and 'sway' now mean the same for the 'rear bar'?

You do not need a front top brace, that is a complete waste of money.

For FWD vehicles, What you do to the front effects the rear and what you do to the rear effects the front in terms of stiffness and control.

Best bang for the buck would be a large rear sway bar and a set of adjustable coilovers, KW V3's come to mind.

lammie200
11-17-2014, 12:52 PM
Being that I have done everything that you have listed, I would do them all in the order that you listed them.

The stock shocks are worthless. You will get a lot more of a stable feeling in the rear end with the Koni's after they are broken in. The anti-sway bar will help with the understeer. You will get a lot more neutral of a feeling out of the steering with it. I would go with the STS bar since it is the cheapest and the easiest to install. The chassis braces are a "must-have" IMHO. Stiffens up the front end greatly. Your car will feel less cheaply designed/built with them in place. They will also add to the preciseness of the steering. I don't have a lower brace bar because I am lowered, but I can see benefits of having one. The upper brace bar is mostly cosmetic, but you might get less vibration out of having one. Also, with the way the engine is mounted you might get a more stable feeling out of the front end.

piney500
11-17-2014, 03:55 PM
Thanks for all the input so far. As stated previously, I have no intention of doing an upper brace bar in the front, so that is a non-issue. After thinking about it I'm probably going to forgo having a front brace bar altogether and just do chassis braces. Since I live in a more rural area it wouldn't be the best idea for me to slam this car given the roads around here. The first 15-20 miles of questionably paved roads getting to the highway from my house could be murder on this car if the profile where too low. However, I was wondering how worth it it would be to at least bring the rear down to the same level as the front. I'm sure that any decrease in elevation would help, but at what point does the cost outweigh the benefit if I'm only going to go so far?

Sales@roadrace
11-17-2014, 04:13 PM
Your car has a Torsion Bar, a sway bar (like on the Dart) is attached to end links, a torsion bar is not (from what I understand). Our Torsion Bars come with super beefy Aluminum Brackets and the bar, so it can bolt right on.

nilfinite
11-17-2014, 05:25 PM
Kind of thought so. Thanks for confirming. I'm assuming that mainly what they do is keep the car from rolling as much?
Yeah exactly, less roll means the car gets less out of sorts when in turns. You also feel more comfortable pushing the car more when it doesn't roll.



Don't plan on racing (at least not for now), just want some increased performance handling. And I do plan on going with CPR's gear. I was also under the impression that lowering the car with the shocks would help the bar do it's job better, so would one not benefit significantly from the other?
So the shocks impact how the car reacts to the road (compression & rebound). It doesn't actually contribute that much to the height of the car. The springs really control the height. I'm not certain if this is true in all cases, but based on personal experience, when I increase the rear ride height (thus increase rear weight distribution), I get more oversteer. So lowering the rear only should actually decrease the effect of the bar. Of course, when people lower the car, they lower both the front and rear.

Abarth Fun
11-17-2014, 06:48 PM
Thanks for all the input so far. As stated previously, I have no intention of doing an upper brace bar in the front, so that is a non-issue. After thinking about it I'm probably going to forgo having a front brace bar altogether and just do chassis braces. Since I live in a more rural area it wouldn't be the best idea for me to slam this car given the roads around here. The first 15-20 miles of questionably paved roads getting to the highway from my house could be murder on this car if the profile where too low. However, I was wondering how worth it it would be to at least bring the rear down to the same level as the front. I'm sure that any decrease in elevation would help, but at what point does the cost outweigh the benefit if I'm only going to go so far?

I had many of the same thoughts and concerns that you have. I've taken my car to track days three times now and I'd like to take it more in the future. But the reality is my car is a streetcar not a race car so daily drivability is very important to me. As a result of this I decided not to lower my car and I kept the stock springs. But I did get the Koni front and rear shocks. I decided that being able to adjust the damping of the shocks was more important to me than adjusting the height of the car. I think the Koni yellow rear shocks made more of a difference than the Koni yellow front shocks. A stiffer rear sway bar will probably also make a positive difference on the track-not so much on the street from my perspective but many people will say otherwise.

I personally believe that some of the large braces added to these cars add weight but not value. People swear by them though. I wish we had more objective ways to get data about these mods rather than the subjective feelings of myself or others. At the very least blind tests where the drivers didn't know what the change was might be useful. There is definitely a placebo effect with some of these mods.

About leveling the rear of your car- I was thinking about doing that too since it would make the car look better. What I found out was that this car does not have much suspension travel in the rear. It's not uncommon on this forum to hear of people hitting the bump stops after adding lowering springs. That wasn't acceptable to me and it is something that you should think about before you lower the car.

Whatever you choose though you're likely to have some fun making modifications. I know I have.

Purgatory
11-17-2014, 09:29 PM
The rear torsion bar alone, will do more for your handling then any of the other options discussed. That and the chassis braces I did first, and between the two, it was like driving a new, firmly planted to the road car. Very noticeable difference in handling, and gave me much more confidence to push the car hard, without the car wanting to dive upon heavy braking.

Just bought the rear Koni's, haven't installed them yet, and do have the under the hood brace. Despite some of the negative remarks, it still helps tighten up the front end of the body of the car. Certainly doesn't hurt to have one, easy to install, and it looks good under the hood. In the category of if you have extra money to spend.

piney500
11-17-2014, 09:32 PM
Again, thanks to all who have contributed. This is exactly the kind of thing I was looking for in order to make an informed decision.

piney500
11-17-2014, 09:36 PM
The rear torsion bar alone, will do more for your handling then any of the other options discussed. That and the chassis braces I did first, and between the two, it was like driving a new, firmly planted to the road car. Very noticeable difference in handling, and gave me much more confidence to push the car hard, without the car wanting to dive upon heavy braking.

Just bought the rear Koni's, haven't installed them yet, and do have the under the hood brace. Despite some of the negative remarks, it still helps tighten up the front end of the body of the car. Certainly doesn't hurt to have one, easy to install, and it looks good under the hood. In the category of if you have extra money to spend.

That is a category I'm completely unfamiliar with, lol. And that's the biggest thing about all these mods is that they're going to take months to acquire so I have plenty of time to compile shared knowledge and select only the most beneficial enhancements. Unfortunately the heart is willing, but the pension check? Not so much. ;)

Tweak
11-17-2014, 10:32 PM
Discussed elsewhere so you already know my take on things... rear torsion bar and front Corsa braces to start and add later as desired. :)

piney500
11-17-2014, 11:19 PM
Discussed elsewhere so you already know my take on things... rear torsion bar and front Corsa braces to start and add later as desired. :)

Yep yep! :)