weight transfer in transient condition

[silente]

Hi all!

I was thinking about a thing a listen for a vey experienced race engineer.

He said that, in his opinion, when you increase the roll stiffness of one axis ( for example the front one), in the first part of the transient you can have more grip on that axis than with less roll stiffness (in our example this means you have more grip on the front in the very firts part of the corner).

From what i know and from some simulation i saw, it is not true, cause anyway you increase the weight transfer. The only things i saw is that, with the same balance but with an higher roll stiffness, the car experienced less grip but reached the maximum of its grip faster...

But, if i made one end stiffer, normally i loose grip on that end, also in transient.

What do you think about it?

Thx

[Goran Malmberg]

In my opinion the load of the outside tire builds up by the time the car roll. During the first time of this period the tire has no slip, and the chassis is under roll in place of pointing in to the corner. The strongest side force is had somewhere in the slip area of the tire, this point is achieved earlier using stiffer setting.
Another comparison is from drag racing. During launch they use "rise" which is sort of jacking that lifts the car thereby planting the tire. A high very direct load build up, but it gives starting grip. Ok, the price is to be paid longer up the strip but the first feet is more important.
The same phenomenon is sometimes used for cornering, the rear rollcentre is raised to get faster load build up to match the turned front wheels.

Guess this is more of a fine-tuning tool and must be balanced against not to hurt the grip later on in the corner. We may use the shocks here to make the effect "time regulated" thereby having less effect for steady state balance.
Regrds
Goran Malmberg