Horizontally disposed dampers - why?

Question for the technically minded people – why are horizontal dampers used on a lot of the supercars?

Whats the advantage or reason for doing it?

Any detailed info would be great, thanks.
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I'm not sure it matters which way you dispose of dampers...



However horizontally opposed dampers are used to relocate the bulky coilover unit from within the suspension arms (and airflow - particularly in open wheelers) to a better location within the bodywork. In terms of supercars that would also make them more accessible to change/set etc. Within the body work they can be in any layout where they can be actuated via bell cranks - this also allows the length/stroke to be optimised as there are less packaging constraints.

 

Plus, it looks butch.

 

Thats the real reason. Why wouldn't you want to show off such beautiful hardware?

 

That is not the reason.

Dampers are mounted that way off of a rocker/pushrod system. This is done on open wheel cars to get the damper spring out of the airstream and to lower frontal area. Furthermore, a rocker system allows one to control the motion ratio and rising rate values of the spring damper unit.

 

Plus, it looks butch.

 

+1

 

Also moves weight to the center of the car, and reduce unsprung weight on the wheels....with more weight in the center of the car, less body roll.

 

Ok so its because it looks butch!

Haha nah thanks guys, very good info.

 

Whats the word I'm looking for.......BUTCH!

Seems there are numerous technical reasons

 

Unsprung weight is mentioned, but for a car like the Enzo (closed wheel) I thought that was the primary reason?

I don't think pulling the weight to the center of the car is going to reduce body roll. On the contrary, it will decrease the moment of inertia around the horizontal/longitudinal axis. Lowering the center of gravity will decrease weight transfer, but moving the shocks in and UP will not. But I don't think that's the point, as I believe it is primarily unsprung weight you are fighting.

 

I think it is still unsprung weight (better: unsprung mass) even though it is sitting horizontal. If the wheel moves, the mass of the damperunit moves too.

 

A primary reason for inboard suspension is aerodynamics in an F1 car...which makes its application in a road car chiefly to reduce unsprung weight.

 

What exactly is considered unsprung weight? My question being, is the effect of changing the placement of the suspension dramatic compared the changes in unsprung weight of wheels, tires, and brakes? Isn't rotating mass the real enemy when we talk about unsprung weight?

 

Unsprung weight includes wheels, tyres, brakes (unless inboard), hub carrier, as well as a proportion of the suspension components. The coil over unit is essentially half unsprung but when transferred inboard it is only the pushrod that is half unsprung - so no, it doesn't have as big an impact on unsprung weight as the wheel/tyre/brake combo.
Reducing the unsprung weight reduces the effort required to move it and therefor keep it in contact with the ground - reducing the rotating mass is part of this but also has the advantage of improved acceleration and deceleration.

 

Thanks

 

I can not understand this, please explain? The half coil over unit still moves when the wheel moves so it is still oscillating mass that needs to be dampened. Logical thinking says unsprung weight is even more because there is also an extra rod and actuator.

 

I was not referring to each half of the coil over unit when describing its weight but treating it as a single object. The coil over unit is connect in two places, the hub carrier (where it is unsprung weight), and the chassis (where it is sprung). Think of it as a gangplank to a boat - one end is on land and one end on the boat and each supports half the weight. So when you move the coil over unit inboard both ends (and therefore its total weight) are supported by the chassis.

This is different from the oscillating mass which, as you rightly point out, increases due to the added components. HTH!