Rear Sway Bar

[dL_ST]

Hey, quick question guys.

I already have a TB performance torsion bar on my car, which is suppose to give the effect of putting a larger rear sway bar on. If I were to get a rear sway would it pretty much be redundant or still beneficial?

 

[alphanumeric]

I actually plan on getting the TB performance torsion bar even though I'm just about to install my eibach sway bars. That coupled with their two point brace and I think the car will be perfectly stiff for my needs. Obviously I think this will still be beneficial as I plan on doing it too. I've been on the track with someone using the 2 pt brace and sway bars in his FiST and he wanted to grab a rear torsion bar also. His FiST is specifically for racing on the track.

 

[BRGT350]

a sway bar is a form of a torsion bar. The rear of the Fiesta ST is already very tail happy, I wouldn't really suggest making it anymore. If you are finding too much understeer, change your driving technique. By making the rear too stiff on a car with an already stiff rear suspension, the car will be very prone to oversteering in a panic situation. Changing driving technique with braking will keep the car balanced in a panic situation and still provide the balance you are looking for. I used to put the biggest bar possible on the back of FWD cars, then I learned how to left foot brake properly and enter corners differently. The understeer went away and the car is far more neutral. No car changes, just driver.

 

[M-Sport fan]

^^^THIS is what I am also thinking about when everyone is throwing the biggest rear swaybar they can find on these cars, let alone compounding the oversteer with a big swaybar AND the rear torsion bar/braces!

I would rather save the weight (even though it is being added in the 'correct place'), and adjust with driving as you are stating.

Maybe everyone wants to 'powerless drift' their FWD car??

 

[CanadianGuy]

Maybe everyone wants to 'powerless drift' their FWD car??

And what is wrong with skidding in the snow or gravel?

 

[M-Sport fan]

And what is wrong with skidding in the snow or gravel?

NOTHING, but this can be accomplished with the stock rear suspension setup easily enough.

Too much swaybar/torsion bar stiffness in the back of this car will enable this on clean, dry, pavement without any effort at all, and maybe even when not wanting this effect.

 

[CanadianGuy]

Too much swaybar/torsion bar stiffness in the back of this car will enable this on clean, dry, pavement without any effort at all, and maybe even when not wanting this effect.

N o t wanting it... No not understanding that.

 

[LilPartyBox]

I actually plan on getting the TB performance torsion bar even though I'm just about to install my eibach sway bars. That coupled with their two point brace and I think the car will be perfectly stiff for my needs. Obviously I think this will still be beneficial as I plan on doing it too. I've been on the track with someone using the 2 pt brace and sway bars in his FiST and he wanted to grab a rear torsion bar also. His FiST is specifically for racing on the track.

This oversteer happiness with said setup is just not true... I say this knowing it is contrary to conventional wisdom. I run coils, PM torsion and 2pt with Cobb sways front and rear. Car is NOT tail happy. It takes a lot to kick the rear out and i haven't found it on the street yet. When the opportunity arises I take off ramps at near double the posted and the car is flat and carving. My 5:30 am morning commute consists of some EMPTY back roads where i throw her into 90* turns at 65 and get a graceful (and f'in awesome) four wheel slide every time. My main issue now is the shitty General AS-03s protest too dam soon but never, EVER do i end up in some oversteering pirouette dance of death [emoji14]

I promise, it just doesn't happen guys. Not even a whiff of what you are describing. I may have to head into an empty parking lot and throw the car around to see what it really takes to get into this tail happy situation everyone said would happen to me with this setup. That being said, I haven't been on a track yet so maybe it just takes way more G's to trigger massive oversteer behavior. All the aggressive street hooning I do and not once has the rear stepped out in some massive way...at all.

I say do it bud. My car is a f*ckin go cart & I love it!

 

[D-resonant]

I already have a TB performance torsion bar on my car, which is suppose to give the effect of putting a larger rear sway bar on. If I were to get a rear sway would it pretty much be redundant or still beneficial?

Adding sway bar on top of TB torsion bar will add more roll stiffness to rear. If you're on factory suspension, this may be a bad idea. It's already tuned for playful oversteer with a quick steering flick. Take heed of [MENTION=1313]BRGT350[/MENTION] 's advice.

The tuned factory suspension (basically on 3k/2.5k springs) utilizes the proportionally higher rear spring rate for higher rear roll stiffness. With coilovers, slight lowering, and on 5k/3k springs, I've found that the FiST understeers without an added rear sway bar.

But if you're dying to try it out, please post back with your suspension setup and results. And please, don't end up laid-out atop an overhead freeway sign.

 

[dL_ST]

My setup is as follows:

Swift R springs on stock struts.
Front strut bar
Traction bar
Cross member bar
Torsion bar
Trunk bar

Car is very neutral as is and I can make the rear come around in a controlled manner. I wouldn't call it "kick out" or "oversteer" because when I drive a Miata for example I can kick out on command if I wanted to. It takes technique to get the rear of the fiesta around in a controlled way.

 

[D-resonant]

Curious what's the Swift R spring rates?

 

[M-Sport fan]

Adding sway bar on top of TB torsion bar will add more roll stiffness to rear. If you're on factory suspension, this may be a bad idea. It's already tuned for playful oversteer with a quick steering flick. Take heed of [MENTION=1313]BRGT350[/MENTION] 's advice.

The tuned factory suspension (basically on 3k/2.5k springs) utilizes the proportionally higher rear spring rate for higher rear roll stiffness. With coilovers, slight lowering, and on 5k/3k springs, I've found that the FiST understeers without an added rear sway bar.

But if you're dying to try it out, please post back with your suspension setup and results. And please, don't end up laid-out atop an overhead freeway sign.

^^^GREAT points about the stock vs. aftermarket dampers/springs used!

 

[dL_ST]

Curious what's the Swift R spring rates?

3.8kg/3.8kg

Front and rear

 

[M-Sport fan]

^^^I thought that the fronts were a little more rate than the rears.

 

[KKaWing]

Originally they listed 212lb/162lb, they now list it as 212lb even.

 

[BRGT350]

correct on adding a sway bar to a stock suspension ST vs a modified suspension ST. As you change springs, tires, dampers, sway bars, and bushings, the balance of the car changes. Either way, changing the driver technique can greatly alter the balance of the car. There are some really great videos online developed by Ford of Europe where they interview the different engineers, including the one who designed the suspension. The video shows the Fiesta drifting nicely around corners. I have found that I can do the same (not as aggressive as shown on the video) by applying left foot braking and balancing the car with throttle and brake, which is exactly how I was taught at Team O'Neil. Even the stock Fiesta, non-ST, can become very tail happy with this technique.

One concern that I have with modifying the suspension on a car with ESC is that the system is designed to work with a certain suspension setup. As you further modify the suspension, you move outside the parameters set by the ESC engineers. At that point, you are better to run the system completely off all the time.

As for running "coils", all Fiesta's run coil springs. Actually, they also all come with coil-over-strut front suspensions from the factory. When I hear people say "I am on coils", that can mean anything from stock to a fully adjustable push-rod suspension. They all run coil springs as opposed to leaf springs, torsion springs, or air springs. I guess that is the suspension engineer in me coming back out.

 

[M-Sport fan]

correct on adding a sway bar to a stock suspension ST vs a modified suspension ST. As you change springs, tires, dampers, sway bars, and bushings, the balance of the car changes. Either way, changing the driver technique can greatly alter the balance of the car. There are some really great videos online developed by Ford of Europe where they interview the different engineers, including the one who designed the suspension. The video shows the Fiesta drifting nicely around corners. I have found that I can do the same (not as aggressive as shown on the video) by applying left foot braking and balancing the car with throttle and brake, which is exactly how I was taught at Team O'Neil. Even the stock Fiesta, non-ST, can become very tail happy with this technique.

One concern that I have with modifying the suspension on a car with ESC is that the system is designed to work with a certain suspension setup. As you further modify the suspension, you move outside the parameters set by the ESC engineers. At that point, you are better to run the system completely off all the time.

As for running "coils", all Fiesta's run coil springs. Actually, they also all come with coil-over-strut front suspensions from the factory. When I hear people say "I am on coils", that can mean anything from stock to a fully adjustable push-rod suspension. They all run coil springs as opposed to leaf springs, torsion springs, or air springs. I guess that is the suspension engineer in me coming back out.

I like (and appreciate) the points you bring up!

I will especially consider the whole ESC system when trying to decide on any aftermarket suspension mods, as you have brought up so correctly.

I also do not get the whole saying "coils" thing (I guess it's an import/sport compact scene nomenclature thing??) either, and why I always refer to them as "coil OVERS", yes, even though technically every strut mounted spring is also a coil over setup.

We should probably be calling them; "adjustable ride height, threaded body/sleeve dampers with small diameter springs mounted to them with adjustable perches", but good luck in getting anyone to use that term for them. LOL

 

[dL_ST]

I like (and appreciate) the points you bring up!

I will especially consider the whole ESC system when trying to decide on any aftermarket suspension mods, as you have brought up so correctly.

I also do not get the whole saying "coils" thing (I guess it's an import/sport compact scene nomenclature thing??) either, and why I always refer to them as "coil OVERS", yes, even though technically every strut mounted spring is also a coil over setup.

We should probably be calling them; "adjustable ride height, threaded body/sleeve dampers with small diameter springs mounted to them with adjustable perches", but good luck in getting anyone to use that term for them. LOL

There is a module you can buy that disables Traction control, stability control, torque vectoring, and understeer control. It's only $200..

 

[LilPartyBox]

Everything is technically a coilover - very true. But the cool kids know that coils means shiny & adjustable too. Across the pond they say 'coily'. Way cooler than our nickname for them. Point being it's a nickname, not a suspension engineering discussion [emoji14]

 

[M-Sport fan]

The problem is that some of the "cool kids" use their shortened term without any reference to suspension, and then it could lead someone to believe that they are talking about swapping in some higher performance IGNITION coils.