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When a car turns left, the centrifugal force puts more of the weight of the car on the right wheels. And yet when watching speeding cars, it's the the left front side of the car that's closer to the ground. What element of a car's build contribute to this?

Update

The motivation for this question is the following. Looking at any car design sketch, and particularly when seeing the underside of cars, the torsion bar is quite prominent. Yet the diameter of the typical torsion bar is so slender that it is puzzling how it can stop anything when the force applied (yes, it's physics!) is a ton of metal. Now I finally have a candidate (physical + engineering) hypothesis. The torsion bar somehow reduces the effect of centrifugal forces. Is this accurate? Indeed race cars show very little tilt, but ordinary sedans show quite a bit, and a tilt to the inside of a turn, not the outside, as one would expect. Does the torsion bar have anything to do with this? If yes, how? If not, what does? (with a future exercise to self: continue seeking what would happen to a car if one removes the torsion bar, hopefully theoretically rather than empirically).

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  • A car will lean "out" in a bend, a bicycle leans in...
    – Solar Mike
    Jul 21, 2017 at 9:53
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    This question doesn't make sense to me, cars do not lean into a turn....
    – GdD
    Jul 21, 2017 at 12:01
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    I'm voting to close this question as off-topic because it's mostly about physics and not about motor vehicle maintenance or repair. Furthermore, the question is very low quality.
    – juhist
    Jul 21, 2017 at 12:42
  • The front inside corner will be close to the ground under braking, but it won't be closer to the ground when turning. If you're watching race cars, there is very little body roll so the difference is negligible. Road cars will have a much more noticeable lean. Jul 21, 2017 at 16:56

2 Answers 2

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Yes, a stiffer torsion bar (aka anti-roll bar) will reduce weight transfer.

Say you're turning left: as the car begins to turn, the weight is shifted to the right, and the right suspension (spring + strut) begin to compress due to the extra load. As the suspension compresses, the anti-roll bar is also pressed down. Depending on the stiffness of the anti-roll bar, some of that downward force will be translated from the right side of the anti-roll bar to the left side. This translated force will cause the left suspension to take some of the load that would have otherwise been displaced by the right spring / strut.

To throw some hypothetical numbers at it, say a hard left corner adds an extra 500 lbs to the right wheel that has a spring rate of 250 lbs/in.

With no anti-roll bar, the right suspension will see all that load, and it will compress 2.0". If the car is equipped with an OE anti-roll bar, lets say 5% of that load is transferred to the left suspension, so the right suspension is compressed 1.9", and the left 0.1". Now say you installed a set of Eibach adjustable sway bars (such as the ones on my car c:). The stiffest setting is somewhere around 25%, meaning the right suspension will compress 1.5", and the left suspension will compress 0.5", giving the physical appearance that the car is much more level, and also providing the left tire with more traction (and reducing the load on the right tire), allowing the car to corner faster.

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The answers to your previous question are still relevant :
The effect of weight transfer or inertia where the object resists the change of direction.

@SolarMike When a speeding car turns left, you see the front of the car tilting also left. Ah, wait, the centrifugal force obviously pushes the car to the right when the car turns left. So the question becomes: what makes the car appear that its weight is loading on the left side? – Calaf 52 mins ago

As you seem to confuse left and right, the weight goes on to the wheel on the Outside of the turn. – Solar Mike 50 mins ago

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  • What previous question are you referring to? Is this a double post?
    – CharlieRB
    Jul 21, 2017 at 12:46
  • @CharlieRB Mea culpa. I replaced the previous question when the wording became irrelevant to the initial one. The present question would have been a near-duplicate, and even then, the answer suggests that I'm not hitting the right question.
    – Calaf
    Jul 21, 2017 at 13:25
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    This could be the best use for furry dice - hang them from your mirror and see if they move left when you take a left turn - I say they will go to the right as per my previous answer.
    – Solar Mike
    Jul 21, 2017 at 14:19

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