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Old 17th July 2007, 19:25   #1
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Default some unanwered queries ...

i guess some of u would have perceived these when ur driving/driven or watching other cars on road...ok heres wat i wanted to know...

why is it that the perception of acceleration is more when ur in the rear seat of a car than in the front seat ?


why does a car's rear sits down ( squats ) when u have a quick get away from a stationary position...? ( i can understand this phenomenon in a rear wheel driven car bcos the torque goes to rear axle and the tires bite onto the road and so the rear dips - but the same happens even in a front wheel drive )

am not sure , but i feel the above 2 phenomenon could be related also ?

experts - pls share ur theories....
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Old 17th July 2007, 19:29   #2
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why does a car's rear sits down ( squats ) when u have a quick get away from a stationary position...? ( i can understand this phenomenon in a rear wheel driven car bcos the torque goes to rear axle and the tires bite onto the road and so the rear dips - but the same happens even in a front wheel drive )
IMO,
The axle/engine/tyres are all attached to the chassis. The body is connected to the chassis via a suspension. So obviously when you floor the accelerator, because of simple physics, the rear should dip.
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Old 17th July 2007, 19:35   #3
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In a front wheel drive when you suddenly accelerate, weight is transferred from the front to the rear. The power on the front wheels is high (or torque) that the front "lifts" slightly and shifts the weight to the car's rear.

Someone could explain this better i feel.
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Old 17th July 2007, 19:38   #4
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Originally Posted by narayan View Post
why is it that the perception of acceleration is more when ur in the rear seat of a car than in the front seat ?
I think this is more psychological as when you drive you are in control and it does not seem that you are going fast as compared to sitting in the rear and watching at the same speeds. There might be a bit of physics too involved as I definitely feel more comfortable in the front passenger seat than in the rear.
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Old 17th July 2007, 23:10   #5
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Originally Posted by n_aditya View Post
In a front wheel drive when you suddenly accelerate, weight is transferred from the front to the rear. The power on the front wheels is high (or torque) that the front "lifts" slightly and shifts the weight to the car's rear.

Someone could explain this better i feel.
ya - so the opposite shud happen in a rear wheel car ...but rear wheel cars wil have much more front lift and back squatting...
in fact some of the americal muscle cars use this principle to do wheelies...
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Old 17th July 2007, 23:42   #6
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Guys,

Isn't there a simple answer to this- INERTIA?

In RWD cars, the front end is raised more because the lever arm is more (Distance from the fulcrum- In this case, where wheels are connected to chasis).

Last edited by CrAzY dRiVeR : 17th July 2007 at 23:49.
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Old 18th July 2007, 09:47   #7
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Crazydriver is correct. It is inertia that impacts the back squatting when the car accelerates from stop suddenly or Front Dipping when we brake hard.
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Old 18th July 2007, 12:50   #8
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Originally Posted by Gordon View Post
IMO,
The axle/engine/tyres are all attached to the chassis. The body is connected to the chassis via a suspension. So obviously when you floor the accelerator, because of simple physics, the rear should dip.
Yes Inertia along with the above information is the reason.
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