Rally Guanajuato Mexico 2013

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Originally Posted by tommeke_B

The longer your suspension travel is, the more fragile it is, without any doubt. If you have an impact, if the distance towards the top mount is 1,5x as much as with another car, the torque on the top mount will be 1,5x as much too. And if the wheel drops deeper, the chance of hitting some edge/stone/whatever is multiple times higher too.

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I don't agree - as further the impact point is, as less the stress is on the higher point.

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Originally Posted by stefanvv

I don't agree - as longer the impact point is, as less the stress is on the higher point.

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If you have a spanner, and you need to loosen a bolt, you will put your hand as far to the outside as you can, right? So with the same force you can get more torque. The same goes for example an object like a stone, if you hit it with the same speed, you will have the same impact, but the torque on the car with longer suspension travel will be bigger than on the one with shorter distance from wheel to topmount.

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Originally Posted by stefanvv

I don't agree - as further the impact point is, as less the stress is on the higher point.

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You are wrong :)
The torque on the mounting point will be bigger. Torque = Force x Distance. So the bigger the distance, the bigger the Torque is. That is just a fact :)

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Originally Posted by stefanvv

how come a car with higher center of gravity will put more pressure on the other wheels, it will just slide it imo.

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It’s simple. A car has a roll center depending of the geometry of the suspension. The car will roll around this roll center and if the center of garvity is higher it will create more torque and therfore a bigger downforce on the outer wheels (radius * sideaway force = torque => more downforce on outer wheels i.e weight transfer).
R/C Car Handling - An Introduction To Vehicle Dynamics (suspension)

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Originally Posted by dupanton

You are wrong :)
The torque on the mounting point will be bigger. Torque = Force x Distance. So the bigger the distance, the bigger the Torque is. That is just a fact :)

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Well, may be this works for Archimedus, who would lift the earth with long enough lever :) But perhaps there are some variables in the middle of that.

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Originally Posted by OldF

It’s simple. A car has a roll center depending of the geometry of the suspension. The car will roll around this roll center and if the center of garvity is higher it will create more torque and therfore a bigger downforce on the outer wheels (radius * sideaway force = torque => more downforce on outer wheels i.e weight transfer).
R/C Car Handling - An Introduction To Vehicle Dynamics (suspension)

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You're absolutely right :)

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Originally Posted by tommeke_B

Of course it's likely some set-up thing, but still, my point is that there is more on a rally-car than just suspension-travel. :) Some people here are almost translating time differences between Ogier and Hirvonen to the difference in suspension travel, and that's not so smart...

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Actually nobody did. They were only misquoted in stating it was the only factor. Of course not, the suspension is an entire package. What can't be argued is the VW has the greater travel over the DS3 it is easy to see in many pictures of the two cars in Mexico.

Nobody is going to convince me a car with only three wheels on the ground in a corner is able to exit faster than one with all four on the surface. It's simple physics and all that was being discussed really.

FCM Suspension Truth v2.3 - How Shocks Work - Rally setups - YouTube

http://www.youtube.com/watch?v=xOtFJ...ture=endscreen

http://www.youtube.com/watch?v=fXZhKAiz2NI

http://www.youtube.com/watch?v=fUrZfumzIe4