Quote:
Originally Posted by smOkin
Are you going to make some?
Would this hi/lo business affect how a car generates mechanical grip through its roll centres? You need the body to roll in order to do this so how would a system treat the forces this would be applying? fast or slow? And if if there is a transit point between hi/lo where the shock stiffens/softens would this affect how the roll centre works?
The only way to know is to try it, ask any R/C company in the world - its great on paper but things can be totally different when tested on the track.
I'm all for innovation though..  |
I have some designs that i think will be effective. whether i actually go balls out and commit myself to making parts and a test rig depends on if i can manage it on my own.
you have got some good questions there... blimey! where do i start.
first of all, slow speed.(slow speed damping is what we have on the standard shocks) that is the main part of the damping that is responsible for the pitch and roll effects on the chassis.
too soft and it gets wollowy and too firm and it gets bouncy and you lose the weight transference and traction etc. so somewhere in the middle keeps the tire where its supposed to be and maintains feel and response.
(typically 'pack' is incorporated into the shocks as its a very effective way of surviving landing impacts but has detrimental effects to the handling at speed when traversing bumps for obvious reasons.)
the slow speed damping would incorporate heavier damping on the rebound stroke. something like 60/40. (many full size cars have twice the damping on the rebound) its a starting point.
this 60/40 ratio is designed to maintain spring compression so that the 'average' ride height is maintained even wile the suspension is waggling up and down over ripples n stuff.
high speed damping. basically this is the opposite of pack.
imagine you are going at speed and you hit a bump. the wheel shoots upward at great speed as it goes over the bump, this fast movement makes the shock 'pack' and too much energy, too quickly, is transferred to the chassis.
this situation will unsettle the chassis and raise the average height and over continued bumpiness will have the buggys wheels off the ground.
high speed damping relieves the shock of this massive load by backing off with the damping effect and allows the length of the suspension to comply with the offending bump and maintain chassis equilibrium.
bump stops would have to be used in the absence of pack to survive heavy landings.
the aim is to improve ride height stability and to keep the tyres in contact with the ground. and if the shocks allow this, then the handling results should reflect your setup.
of course, the theories have to be tested. I would make a test rig to do this. i couldn't rely on my driving skills as they are not too good. i would have to find someone good to do track testing for me.