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Discussion Starter #1
I see many here touting the benifits of upgraded coil overs for reducing body roll. Why is it I don't see much said towards sway bars? Seems like an obvious solution to body roll. Any thoughts?
 

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From a Wiki...

Anti-roll bars provide two main functions. The first function is the reduction of body lean. The reduction of body lean is dependent on the total roll stiffness of the vehicle. Increasing the total roll stiffness of a vehicle does not change the steady state total load (weight) transfer from the inside wheels to the outside wheels, it only reduces body lean. The total lateral load transfer is determined by the CG height and track width.

The other function of anti-roll bars is to tune the handling balance of a car. Understeer or oversteer behavior can be tuned out by changing the proportion of the total roll stiffness that comes from the front and rear axles. Increasing the proportion of roll stiffness at the front will increase the proportion of the total load transfer that the front axle reacts and decrease the proportion that the rear axle reacts. In general this will cause the outer front wheel to run at a comparatively higher slip angle, and the outer rear wheel to run at a comparatively lower slip angle, which is an understeer effect. Increasing the proportion of roll stiffness at the rear axle will have the opposite effect and decrease understeer.

Drawbacks

Because an anti-roll bar connects wheels on the opposite sides of the vehicle together, the bar will transmit the force of one-wheel bumps to the opposite wheel. On rough or broken pavement, anti-roll bars can produce jarring, side-to-side body motions (a "waddling" sensation), which increase in severity with the diameter and stiffness of the sway bars. Excessive roll stiffness, typically achieved by configuring an anti-roll bar too aggressively, will cause the inside wheels to lift off the ground during very hard cornering. This can be used to advantage: many front wheel drive production cars will lift a wheel when cornering hard, in order to overload the other wheel on the axle, limiting understeer.

Makes sense, no?
 

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Yea a rear sway bar would have the effect of flattening the rear under cornering but also shifting the weight away from the rear. Shifting weight away from the rear isn't a great idea in a mid-engine rear drive car... you want to power out of turns, squatting (within reason) is good.

Note: Many Elige owners will actually increase the front bar size which tends to shift more weight bias to the rear.
 

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I suspect a stiff rear sway bar would make snap oversteer a bigger problem, I know stiffening my front sway bar reduced snap oversteer (a little).
 

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I suspect a stiff rear sway bar would make snap oversteer a bigger problem, I know stiffening my front sway bar reduced snap oversteer (a little).

I would agree that a stiff rear sway would increase oversteer. But I have considered a very modest read sway bar. A very light, adjustable bar use to balance/tune out some of the understeer.

Only two things have stopped me.

1) This winter my couch seems to have generated an incredible gravitational vortex. Time to get off my backside and start moving.

2) I milled the front uprights and for the street driving I do with the car it is handling pretty darn good.
 

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Discussion Starter #9
Not trying to rewrite the book. Just looking for clarification an lack of factory rear sway bar.
Seems like ma
Many are going to performance coil overs. Trying to consider what is best option.
 

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One rollbar lets you adjust relative roll stiffness because you still have the springs as an independent variable on both ends. I suspect lotus decided they could drop the wieght of the setup and still get the handling balace they wanted. The factory cars have quite alot of roll anyways but the suspension geometry is pretty good so it is ok. The front standard sway isnt very stiff either.

Sent from my DROID RAZR using AutoGuide.Com Free App
 

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I had a somewhat stiff one in the rear of my 88 Fiero (which I later turned into an Elise kit /troll)

It made it handle pretty weirdly. It did make it feel a bit nicer in some corners, but in other corners the steering wheel would randomly jerk towards the inside of the turn (is that what snap oversteer is?). It might have been from bumps in the road or maybe something else, but it was definitely strange. Would not recommend.
 

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Your Elise didn't come with a sway bar?
OMG How do you drive and keep it on the road?
You need to get one immediately.
Have you tried to find an OEM one lately? No one has one. They're impossible to find!
I happen to have one spare OEM that I can sell you for cheap.
 

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Sorry.
Actually it is a great question but for days I have been dying to say that. Thanks for letting me get that out of my system - carry on.
 

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Not trying to rewrite the book. Just looking for clarification an lack of factory rear sway bar.
Seems like ma
Many are going to performance coil overs. Trying to consider what is best option.
The way the questions are written it almost sounds like the body roll is bad.
Which some roll is not bad, and actually helpful.
 

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Lotus have set the car up to have a understeer tendancy. This is part of the NO swaybar setup. As I understand it, a swaybar or heavier swaybay adds oversteer.
 

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Camber and toe adjustment are your friends! Also lighter!!
 
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