Good morning community,
I try to understand the springs and I am confused and this makes me crazy.
I read here a lot about tuning the springs but I cannot understand something I will explain, please tell me if I am right or wrong.
I will use the example used in the forum many times.
Weight - 2000
Weight distribution 55%
Front spring = (2000 x 55%)/2 = 550
Rear spring = (2000/2)-FS=(2000 x 45%)/2 = 450
So far so good.
Then I run a test when the car is still and checked the springs’ telemetry.
- I set F and R springs to max stiffness. Telemetry showed offset point 0.5 when car is still
- I set F spring to min and R spring to max - offset again 0.5
- F spring min R spring min - offset 0.5
- F spring max R spring min - offset 0.5
I monitored many hours the springs’ telemetry and my conclusion is: (not sure right or wrong):
There is a bar, half white, half black. When the car is turning to left it tends to careen to its right side. Right springs compress(shrink), left - expand. And vice versa.
So the black sector shows how much the spring can shrink, the white - how much to expand.
If offset is 0.5 then the sprig can shrink as much as it can expand, something like the spring is in middle position.
Then, when I change the stiffness the offset is always 0.5 when the car is still. This is only possible when if I change the stiffness I also change the length(height) of the spring. Softer spring, longer spring, stiffer spring shorter spring. Because if the length of the spring is constant and I change the stiffness, then the offset should change also. For example if stiffness is 500 and offset is 0.5, and I change stiffness to 300 (softer) the spring should shrink and the offset should be less than 0.5, lets say 0.4. But it is still 0.5.
So, never mind what ratio F/R and what stiffness I set, the offset when the car is still is always 0.5. So whatever stiffness and ratio I set to the springs, the car’s weight is automatically proportionally distributed to the springs
So what is the point of the above calculations from the example? There is point if the springs length is constant, when I change only the stiffness, so I can set the offset to 0.5.
I run many tests monitoring the springs telemetry and watching the offset. There was almost no change of the offset between soft long springs and stiff short spring.
I am very confused what information I can gather from the springs telemetry and this makes me crazy.
So my final conclusion regarding springs tuning is:
Regarding car’s weight distribution springs’ tuning is not important. The weight is always properly distributed never mind what figures I set.
Regarding overseer/understeer is very important, especially the ratio F/R.
Softer springs - slower turns, but absorbing the uneven parts of the track and that way keeping the speed.
Stiffer springs - faster turns, but if too stiff cannot absorb the bumps and the car jumps and speed drops very fast.