Video: The difference sway bars make on the track | Track test

My takeaway,I would have liked to have seen deeper discussed, other than the one example of the rear inside tire lift with a stiff rear SB on a front engine car, is that all swaybars ultimately load the outside tire patch greater than the inside tire.  That is the complete opposite of what many novices believe. That may result in a flatter chassis with all its inherent possible camber benefits, but that increase of greater tire imbalance also lowers the available total axle's grip, ignoring any increases from any better camber found.

I really liked those greaseable alum billet SB mounts. Curious if they are available ala carte?

Just like guys that post videos in car groups. If you're going to post a nearly 20 minute long video, give us a few paragraph summary to so I can tell if this something I already know, or if it's worth my time to watch. 

Any chance there will be a video on anti-roll bars on a front wheel drive car in the future?

I started laughing the second I heard you had to drop the crossmemebers to install the sway bars. Hmmmm I vaguely recall someone mentioning German cars being needlessly complicated........sorry couldn't help myself.

So on the subject of sway bars; I installed a bigger set of bars on an otherwise stock Miata and actually made it slower at autocross. It was my Showroom Stock car that had an open diff, the bigger bars resulted in wheelspin off every corner.

On our D-sports racer the suspension was designed in a way that it didn't need Sway bars. Basically it had long control arms on a narrow chassis.

In reply to SeniorPBA2B :

Not a video, but here's a post when they changed the sways in their project GTI.

https://grassrootsmotorsports.com/project-cars/2017-golf-gti/fitting-stiffer-sway-bars-that-wont-ruin-our-gtis/ 

edit to add:  link to video.   https://grassrootsmotorsports.com/project-cars/2017-golf-gti/can-a-rear-sway-bar-really-make-our-gti-faster-on/

Tom1200 said:

So on the subject of sway bars; I installed a bigger set of bars on an otherwise stock Miata and actually made it slower at autocross. It was my Showroom Stock car that had an open diff, the bigger bars resulted in wheelspin off every corner.

Yeah this is definitely the risk with open diff cars, and it was something we were definitely worried about with the BMW. So far, though, it feels like we've avoided disaster in the diff department. I still think a proper mechanical diff would improve things once we coded out the E-diff functionality, but for now at least it appears we haven't made thuings worse.

Tom1200 said:

I started laughing the second I heard you had to drop the crossmemebers to install the sway bars. Hmmmm I vaguely recall someone mentioning German cars being needlessly complicated........sorry couldn't help myself.

So on the subject of sway bars; I installed a bigger set of bars on an otherwise stock Miata and actually made it slower at autocross. It was my Showroom Stock car that had an open diff, the bigger bars resulted in wheelspin off every corner.

On our D-sports racer the suspension was designed in a way that it didn't need Sway bars. Basically it had long control arms on a narrow chassis.

I've always heard your spring rates should be the first part of the equation to determining how the car handles and the sway bars are to fine tune it. Not the other way around.

z31maniac said:

I've always heard your spring rates should be the first part of the equation to determining how the car handles and the sway bars are to fine tune it. Not the other way around.

There are two trains of thought on this.

1. Is make the car as soft as possible, for the purposes of suspension compliance and use larger bars to control the roll.

2. User a higher spring rate to control roll and then fine tune the balance with smaller bars.

The aforementioned sports racer used 25" long control arms mounted on a 18" wide chassis. It also used a rising rate suspension which allowed for really complaint suspension without the huge amount of chassis roll. All of these things negated the need for sway bars. As I set a class lap record with the car I'd say it worked very well. Unfortunately you can't do this on the production based cars most of us run. 

If I am picking between the two suspension set ups I noted it's going to be the first one as I ride the kerbs religiously. My experience in really stiffly sprung cars is that slamming the kerbs tends to upset them. 

In reply to Tom1200 : Any aero at play being impacted by a soft set-up and pitch being very braking /acceleration sensitive. I lean (pun intended) towards higher spring rate thinking.

Tom1200 said:

z31maniac said:

I've always heard your spring rates should be the first part of the equation to determining how the car handles and the sway bars are to fine tune it. Not the other way around.

There are two trains of thought on this.

1. Is make the car as soft as possible, for the purposes of suspension compliance and use larger bars to control the roll.

2. User a higher spring rate to control roll and then fine tune the balance with smaller bars.

The aforementioned sports racer used 25" long control arms mounted on a 18" wide chassis. It also used a rising rate suspension which allowed for really complaint suspension without the huge amount of chassis roll. All of these things negated the need for sway bars. As I set a class lap record with the car I'd say it worked very well. Unfortunately you can't do this on the production based cars most of us run. 

If I am picking between the two suspension set ups I noted it's going to be the first one as I ride the kerbs religiously. My experience in really stiffly sprung cars is that slamming the kerbs tends to upset them. 

 

 

After experiencing a low spring rate setup vs a high spring setup on the same car, same track, same tires.........I go for #2. I also use the kerbs where it makes sense to. Turn 10 at Hallett for instance, you don't want to touch those. Turn 1, the driver seat needs to be over the kerb for the best exit speed. 

"Every time you miss a kerb, God kills a kitten."