Sway bars

[Kodiak]

Thinking about adding these to the Mk4. Do the the sway bars tighten the car up to much for street use where the ride is compromised . Mk4 427W Tkx Irs 17s .

[Tbev]

I don't have an answer to your question as I am still in the build process, but if you decide to go with the sway bars+69 I have a brand new front sway bar that I do not need and will be looking to sell. PM me if interested.
Tony

[facultyofmusic]

If you haven't completed your rear suspension install yet, install the rear sway bar mount ASAP. Retrofitting the sway-bar mounts was the single biggest PITA. In hindsight I should have asked FFR if I could just order the sway-bar mounts separately when I ordered the kit itself.

[MB750]

From watching the options video, adding a sway bar in the front adds traction in the back (and vice versa) so I ordered the front sway bar option for my build. From what I've seen these cars need as much traction help as they can get.

Consequently, I didn't see an option for a rear sway bar.

[nucjd19]

I have a 3 link and added the Forte front sway bar kit to help with the oversteer I was feeling when cornering. The pros on here recommend against the sway bar front sway as it can put too much understeer in the rig and "push " into corners. I think where this is apparent is when auto cross driving or track days. I have been putting miles on the road in gelcoat so I am not pushing hard into the corners and therefore can't get a lot of feed back on it but at legal speeds it seems to help with the oversteer. I will know more when I get it on an auto cross course.

[CraigS]

I don't feel that bars make it too stiff but that is all personal opinion, personal prior experience.
BTW, this info that you put into your post, "Mk4 427W Tkx Irs 17s" can be added to your signature so you won't need to type it every post. Go the very top of the page and click 'Settings'. On the left side under 'My Settings' click 'Edit Signature'. Type your info into the window and click 'Save Signature'.

[Jeff Kleiner]

From watching the options video, adding a sway bar in the front adds traction in the back (and vice versa) so I ordered the front sway bar option for my build. From what I've seen these cars need as much traction help as they can get.

Consequently, I didn't see an option for a rear sway bar.

I think you may be misunderstanding. Sway bars have no effect on straight line traction, only cornering. These cars have a moderate understeer with the factory spring rates and no bars---adding only a front anti-roll bar without a corresponding change to the rear either via a bar or higher spring rate will exacerbate that and make it push even worse. Choose your changes and additions wisely ;)

Jeff

[Jeff Kleiner]

I have a 3 link and added the Forte front sway bar kit to help with the oversteer I was feeling when cornering. The pros on here recommend against the sway bar front sway as it can put too much understeer in the rig and "push " into corners. I think where this is apparent is when auto cross driving or track days. I have been putting miles on the road in gelcoat so I am not pushing hard into the corners and therefore can't get a lot of feed back on it but at legal speeds it seems to help with the oversteer. I will know more when I get it on an auto cross course.

Jon,
That’s throttle oversteer. My comments regarding over/understeer are in reference to steady state which can be on throttle or off—an abrupt change from on throttle to off or vice-versa while cornering will elicit a change (usually to immediate oversteer!). What happens is you head into a corner a little hot and feel the front end push; i.e. the car isn’t turning, so you think “oh, I need to slow down” so you jump out of the throttle and the back end comes out. That’s a different kind of oversteer!

Cheers,
Jefg

[Hoooper]

Thinking about adding these to the Mk4. Do the the sway bars tighten the car up to much for street use where the ride is compromised . Mk4 427W Tkx Irs 17s .

I dont think so. I dont know how it compares to the ride without bars but I think the ride is perfectly fine with sway bars front and rear. IRS rear with koni DAs, miata front sway bars front and rear.

[Bob Cowan]

Anti-sway bars are used as a tuning device. Adding more or less bar at each end can make the car more neutral in the corners.

Remember that a bar connects the two sides together, and uses the unsprung weight of the inside in a corner to push down on the unsprung weight of the outside. It makes the "independent" part of the IRS less independent. That's OK on a race track where you don't have to deal with potholes, rough transitions, RR tracks, etc.

As for ride quality, it depends on what your set up is to begin with. When I was racing my FFR, I added stiffer springs. Then the sway bars made it even stiffer. For the street, I would disconnect the bars. Didn't need them. And it handled rough roads and transitions much better when the suspension was allowed to fully work.

[Jeff Kleiner]

For anyone who doesn’t already know this—-when Bob talks smart people listen :)

Jeff

[GoDadGo]

Things To Consider:

> All of our cars leave the Factory Five facility pretty much the same; however, each ends up being a totally unique car at completion.
> A Small Block Ford (302) with aluminum heads would have a far different weight distribution compared to one with an All Iron FE Big-Bock.
> Spring rates, front-end alignment settings, and tire sizes along with tire compounds choices also are a big part of the equation.
> Add in rear suspension type (4-Link, 3-Link, or IRS) and things change a lot from car to car and in a very big way.
> Will a 302 aluminum-headed car with 245's on the front push more if it has 315's on the back compared to the same car with that Iron FE?
> How would that compare to somebody running 275's and 315's stack up when it comes to under vs oversteer for different engine weights?

No I don't have the answers, nor do I even have the questions but there are a lot of factors to consider.

Good Luck!

[NAZ]

Like Bob said, ARBs are chassis tuning aid. Unless you have a specific reason that you need one (and know how to use it), I suggest you don't add one -- especially one that is not adjustable. Every chassis adjustment affects other areas and adding an ARB adds complexity.

Not all race cars run ARBs, nor do they need to. I run front & rear ARBs on one of my race cars and none on the other. Two very different cars built for two very different racing series. An ARB is not simply to reduce body roll, nor is it the only way to affect body roll or even the best way. Remember, it's only a tuning aid.

As JR said, an ARB increases spring rate and higher spring rates reduce traction. Adding load (weight) to a tire increases traction -- stiffer springs do not add load. As Jeff said, have a car that pushes and install a front ARB, it will increase the push. The goal is to have a balanced car with as much traction as you can get. Sometimes an ARB helps but it will more likely hinder performance if not selected carefully to augment your particular car. There is no one size fits all ARB and like Steve said, all our cars are different. There is no way that a manufacturer can build a bar that works perfect in every application. If your bar is not adjustable you have just made your life more complicated.

Choose wisely. But even a wrong choice is a learning opportunity so don't be afraid to experiment as much as your wallet will allow.

[GTBradley]

Glad to see this thread started. I was going to do one myself because I have just installed a front anti-sway bar on my Mk4. I've driven the roadster 10,000 miles and auto-crossed it last summer. All indications are that it oversteers, so I added the front bar with no pre-load (no tension on the bar). Now the question becomes, how to adjust the bar if needed. I can see that the ARB could be adjusted in in atleast eight different combinations, so is there a rule-of-thumb that people use after a run at AX?

[nucjd19]

Jon,
That’s throttle oversteer. My comments regarding over/understeer are in reference to steady state which can be on throttle or off—an abrupt change from on throttle to off or vice-versa while cornering will elicit a change (usually to immediate oversteer!). What happens is you head into a corner a little hot and feel the front end push; i.e. the car isn’t turning, so you think “oh, I need to slow down” so you jump out of the throttle and the back end comes out. That’s a different kind of oversteer!

Cheers,
Jefg

Thank you for the clarification sir! Much appreciated. I wold love to do some laps with you first sitting in the passenger seat and then the pilot seat with your instruction. That type of teaching would be worth it's weight in gold :)

[Bob Cowan]

Nothing will make you faster quicker than an instructor in the right seat.

[Bob Cowan]

Bob,
For clarity you might think about your explanation in terms of the dynamics of the masses involved. In a corner the unsprung weights (wheel/tire assemblies) are static on the ground, no vertical displacement.They do not lift or push anything. The sprung weight (chassis) is dynamic in a turn, dropping on the outside and lifting on the inside.
As the outside chassis drops it twists the ARB putting a lifting force on the inside wheel/tire. It is not an asset to lift the inside tire, it is already somewhat unloaded.
The asset is that the ARB twist is adding spring rate to the outer suspension, resisting weight transfer.

In terms of ride quality, mentioned above, if the wheel/tires bump together, like a speed bump, they have no effect on the spring rate or ride quality.
If one wheel/tire is lofted by a bump, the ARB twist adds to the spring rate making the chassis lift more on that corner.
jim

We could go in to a long technical discussion about ASB's, roll center, spring rates, etc. But I was trying my best to keep it simple and easy to understand. :)

[chjort]

We were told in Build School that sway bars are unnecessary for street cruiser use.

[J R Jones]

Thank you for the clarification sir! Much appreciated. I wold love to do some laps with you first sitting in the passenger seat and then the pilot seat with your instruction. That type of teaching would be worth it's weight in gold :)

Jon, There are driving techniques and then there are driving techniques. As Jeff states sudden inputs of too much force may upset chassis and the contact patches. The front tires will grip with a given amount of friction that is challenged by brakes and slip angle (steering). Donohue called it the friction circle. As NAZ states above, load increases traction. So brakes can shift load to the front tires and increase the available friction. This is especially effective with ABS. Anticipating that the front tires will understeer, a bit of brake load may keep them hooked up as steering is added. Track straights and corners provide more time for braking strategy, autocross, not so much.
I can attest that if you have not slowed enough, and are not yet to the point of un-steering, and you release the brakes....cones will die.
BTW Jeff's comment on decel applies to big GD engines and manual transmissions, causing the rear wheels to slide. Maybe automatics are not just for drag racing?
jim

[frankeeski]

We could go in to a long technical discussion about ASB's, roll center, spring rates, etc. But I was trying my best to keep it simple and easy to understand. :)

You know what I love about you Bob, and have learned to respect? You're a do'er, not a talker. Nit'pickn technical jargon just isn't in some of our DNA. We go out, we race and we take the experience and learn from it. Others tend to talk things to death. Thank you, from one do'er to the other.

[Kodiak]

Thanks for all the reply’s lots of good info here as always .

[Jeff Kleiner]

You know what I love about you Bob, and have learned to respect? You're a do'er, not a talker. Nit'pickn technical jargon just isn't in some of our DNA. We go out, we race and we take the experience and learn from it. Others tend to talk things to death. Thank you, from one do'er to the other.

See post #11 ;)

Jeff

[WIS89]

For anyone who doesn’t already know this—-when Bob talks smart people listen :)

Jeff

Jeff-

I agree with your assessment about Bob. However, can stupid people listen too? Asking for a friend! :cool: :cool: :cool:

Regards,

Steve

[Jeff Kleiner]

Jeff-

I agree with your assessment about Bob. However, can stupid people listen too? Asking for a friend! :cool: :cool: :cool:

Regards,

Steve

If stupid people listen (and most importantly heed) they might just become smart!

Jefg

[NAZ]

Glad to see this tread started. I was going to do one myself because I have just installed a front anti-sway bar on my Mk4. I've driven the roadster 10,000 miles and auto-crossed it last summer. All indications are that it oversteers, so I added the front bar with no pre-load (no tension on the bar). Now the question becomes, how to adjust the bar if needed. I can see that the ARB could be adjusted in in atleast eight different combinations, so is there a rule-of-thumb that people use after a run at AX?

Looking at the photos of the ARB you installed, it appears to be a solid 1-piece bar with no adjustment. Adjustable ARBs typically come as a solid 1-piece version with multiple attachment holes or a 3-piece design with multiple holes in the replaceable arms. To make the bar stiffer you mount the links in the holes closer to the pivot point (the attachment point on the chassis in your case). To adjust for less anti-roll authority, mount the links farther from the pivot. Here's a couple of photos of adjustable ARBs.

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I will tune handling balance with spring rates and other suspension adjustments before adding an ARB. In some cases, an ARB allows me to use softer spring rates which increases traction.

[GTBradley]

It has no extra holes, but it does have adjustment at the control arm attach point, is that not used after install?

https://thefactoryfiveforum.com/attachment.php?attachmentid=162843&d=1645376052

[NAZ]

GT, your attachment doesn't seem to work for me. But if you are referring to the rod ends on the links, those are for adjusting the pre-load or in your case, no pre-load. They are not for adjusting anti-roll authority. Due to manufacturing tolerance stack-up, you may need to adjust these to eliminate any torsional loading on the bar at static ride height. Also, some race cars are set-up with different ride height side to side or use a preload on one side of the bar. So it's common to have adjustable connecting links. Dirt cars will even use a chain on one side of a front ARB so it only works in one direction. But for a street car, you want equal ride height side to side and no pre-load on your bar. So use these adjustable links for that.

It is what it is -- a non-adjustable ARB. Now what? If the ARB fixes the loose condition you were working on, then great -- you got lucky. Chances are it didn't and you ether have a push or you're still loose. Welcome to chassis tuning! It's an iterative process and helps if you understand how all the parts work together. If you're simply dealing with a loose condition (don't confuse this with loose during aggressive acceleration -- that's a different problem), then lower spring rate on the rear or lower tire pressure may help gain some traction in the rear. Most folks run too much spring and too much air pressure.

I have ARBs in my tuning toolbox but they are not anywhere near the first thing I try. They can mess up a car's handling as fast as you can install them. And thinking you can install one without other changes is usually not realistic.

[J R Jones]

Brad, your attachment does not open for me.
If the control arm link mount is a range of holes from the pivot shaft to the ball joint, then the spring rate of the ARB would be greater near the ball joint and less near the pivot shaft due to (control arm) lever advantage. I have never seen that configuration.
jim

[GTBradley]

I figured I was starting with a basic sway bar, especially considering it is less than half the expense of the more adjustable one like Breeze has. In the few short drives I’ve done I feel as though I have better cornering stability at the rear wheels already. I have investigated a range of tire pressures, but have the stock springs from FFR. The way the car breaks traction in a steady state turn is at the back, so I’m convinced it’s oversteer I’m dealing with. I’ll give it a try at AX when things start to open up soon and let you know how it goes. If it doesn’t help, or worse, causes a push I’ll look at springs and a better front bar.

Thanks for the input guys. Also, what will softer springs do to the ride quality for daily use?

[NAZ]

OK, sounds like a loose condition and a front ARB may help, but again, it's not the only way or even the best way to deal with this handling issue. I actually prefer a little loose and absolutely hate a push. A little loose can be fast.

If there is one overarching theme in chassis design and tuning it’s that all the components must work together to maximize performance. That’s why we have to look at how all the different parts and adjustments integrate and why focusing on just one area or one part without regard to integration usually leads to less than stellar performance.


You asked what will softer springs do to the ride quality for daily use? It will be smoother riding and provide better traction which can reduce stopping distance and up to a point, improve handling. Of course, shock damping and spring rate must work together to maximize that improvement. But don’t make large changes in spring rates on one end as suspension frequency front to rear plays a significant part in handling. You could end up with a car that pitches up and down over bumps like a tuna boat in rough seas. You can Google suspension frequency to learn more. I hope you and others following along will as it's an important topic.


As I’ve said before, you can balance the car’s handling (loose to tight) by using spring rates without an ARB. What you are doing is affecting traction at one end or another (or one corner on a roundy rounder or drag car) by changing the spring rate. And here’s some info to help understand why spring rates affect traction. https://www.roadandtrack.com/car-culture/a10385629/why-stiff-suspensions-have-less-grip/

BTW, the tires are also part of the suspension system and affect the overall spring rate at each corner as well as traction and handling. There's a lot to learn about tires too.