Originally posted by modellor
I agree with you. But is this not what I just said.
But using just the springs to compensate for bumps on some tracks is not enough as the softer springs will allow the car to bottom out and in effect reduce the overall grip and handling of the car in corners. For this reason we allow chassis flex to absorb some of the bumps (like on the first cars with no suspension - the secret is knowing where and how much flex to build in) so that harder springs can be used for better cornering ability along with softer tires.
Understood, but the differences we are talking about here, is that any chassis flex is uncontrolled and therefore must be considered in addition
to any suspension settings made.
In your first example (to compensate for bumps), I'm imagining a car moving along a flat track and then encountering a bump.
I'd think it is likely that the flexible chassis will hit the ground first - since it will be bending in the middle, presumeably. There is no damper on the chassis. I say the remedy is in springs and damping - something you can control.
In your second example (the first cars with no suspension), while the environment is somewhat more controlled, the situation is still the same. In these cars (and I'm not familiar with them), the tyres essentially are
the suspension - a bit like current F1 cars.
In either of these cases, we must remember that there is only a finite amount of grip available. You can't suddenly find some extra grip because the chassis moved as opposed to the spring. In fact you can move the tyre to the track with a spring much faster than by moving the whole chassis. The vast differences between sprung and unsprung weight is the primary reason we have suspension systems, surely.
When you talk about building in some chassis flex, the ramifications can be extremely difficult to control.
Can the flex can be limited to a single plane?
Can you permit single plane flexing and at the same time maintain torsional rigity?
Can you control squat and dive at either end of this chassis (the wave effect) together with their interactions?
Since the chassis is acting as a spring, how do you damp it?
Generally, Im saying that, idealy, any suspension settings made must be performed on a stable platform - any flex in that platform must diminish the relevance and effectivness of those settings as it is uncontrolled and largely uncontrolable.