Thread: Sway Bars

Originally Posted by rammypluge

Defender-Elchtest: Wirbel bei den Handlern - auto motor und sport

So much for sway bars! I would love to see the test video, is there one?

Originally Posted by manic

So much for sway bars! I would love to see the test video, is there one?

I tried to find a video but failed.

A wider track and four wheel independent suspension would greatly reduce its rollability.

Originally Posted by manic

That was not a moose test, he was certainly trying to roll it for TV. Watch the internal cam, he starts to shift the weight back across the vehicle and then at the most devastatingly effective moment he uses both his arms to wrench the steering wheel right round to full lock. He effectively threw that rrc over his shoulder!

I would have to check it again, but if he did that i wouldnt be surprised and it could be justified under a worse case scenerio. People will feel the impending roll and try to avoid it if they can, but in a worst worst case scenerio they cant. Its easy to not make it roll.

A full moose test with cones could be better. But i am not wholeheartedly sold on the moose test since it is making cars harsh riding, understeery and flexless.

Originally Posted by rammypluge

The RRC driver in the video was presumably trying to stay on the 'road' and also avoid any oncoming traffic. The moose test involves swerving back into ones lane.

Most passenger cars need to be tripped to roll over, but many 4wds are a different story. However, most 4wds on showroom floors with esp would be hard to roll without a trip.

Less body roll reduces the risk of simple harmonic motion, where two or more factors combine and compound to create a rollover.

All that being said, many people are now blindly obsessed with minimal body roll, at the expense of many things, including ride comfort, off road ability and off road safety. Its about striking the right balance, and these days swaybars are typically taken too far.

As manic said he really wound on a heap of lock to induce that RRC to basically trip over it's own feet!
I think it'd be highly unusual to have the natural frequency of the suspension to match the tyre spring rate though, but it can happen.
[edit] I wonder what tyre pressures they were running in that RRC too? Go too low and the tyre folds over basically rolling too far off the rim. Sometimes the rim can hit the bitumen digging in and over you go.

Yep, agree with that last par, I think what happens is that some manufacturers go with really soft springs for a low wheel rate for ride compliance and then use possibly too stiff ARB's to balance the handling and reduce the wallow.
It also always amazes me how little rebound a lot of utes run in the rear dampers too. They just tend to pogo down the road.

I find it interesting that manufacturers have moved away from the zero roll of Active Suspension and the ACE system in the D2.
I think we need a bit of roll to help feel what's going on.

A lack of roll definitely feels better to most, and that includes experienced race drivers.
One of Schumachers advantages was the ability to run a little less low speed bump in his dampers as the bit of roll didn't worry him.
It let the car comply a little better, the roll transition took a little longer and generated a little more mechanical grip.

Originally Posted by rick130

As manic said he really wound on a heap of lock to induce that RRC to basically trip over it's own feet!
I think it'd be highly unusual to have the natural frequency of the suspension to match the tyre spring rate though, but it can happen.
[edit] I wonder what tyre pressures they were running in that RRC too? Go too low and the tyre folds over basically rolling too far off the rim. Sometimes the rim can hit the bitumen digging in and over you go.

Yep, agree with that last par, I think what happens is that some manufacturers go with really soft springs for a low wheel rate for ride compliance and then use possibly too stiff ARB's to balance the handling and reduce the wallow.
It also always amazes me how little rebound a lot of utes run in the rear dampers too. They just tend to pogo down the road.

I find it interesting that manufacturers have moved away from the zero roll of Active Suspension and the ACE system in the D2.
I think we need a bit of roll to help feel what's going on.

A lack of roll definitely feels better to most, and that includes experienced race drivers.
One of Schumachers advantages was the ability to run a little less low speed bump in his dampers as the bit of roll didn't worry him.
It let the car comply a little better, the roll transition took a little longer and generated a little more mechanical grip.

If the natural frequency of the suspension matches the frequency of the body roll, a kind of pendulum effect. If the body has rolled over to one side and then you start a swing the other way, it creates maximum momentum. Like when two people use a trampoline to launch one person super high.

I agree a lot of utes dont have enough rebound, although i reckon a lot of trucks and some passenger vehicles are lacking too.

Body roll can help drivers judge the magnitude of the cornering forces, and create a softer, more forgiving (more recoverable) transition from grip to slide.

Originally Posted by rammypluge

.........

Body roll can help drivers judge the magnitude of the cornering forces, and create a softer, more forgiving (more recoverable) transition from grip to slide.

Yes - a decent amount of body roll will frighten the driver into slowing down!

Originally Posted by rammypluge

I tried to find a video but failed.

A wider track and four wheel independent suspension would greatly reduce its rollability.

Thats a lot of modification work and engineering to change a defender/rrc to that.....

Originally Posted by uninformed

Thats a lot of modification work and engineering to change a defender/rrc to that.....

Training wheels then.