How do i use Springs and damper settings?

Ok guys, i figured out that springs decide how far the suspension will go and dampers how fast.
But how do i use these settings?
I know i can use them to correct under and oversteer, but how do i know how to make them stiffer or softer when it comes to bumpy surfaces?

I’ve been testing on the last corner of SEB ring, as that is pretty bumpy and i can test the surface and the body roll at the same time, but i am having trouble figuring out what signs to look at for what adjustments. So basically, what should i look at to decide on what to adjust on my springs and dampers?

Soften springs and it’ll absorb bumps better. Soften too much and you’ll have some serious bouncing similar hydraulics on a donk. It’s pretty funny when you drive a soft springed car on Lemans buggati and get the the left hander after the back stretch.

For more oversteer have rear rebound/bump settings greater than front for both. Opposite is true for understeer. With these what you should do for bumpy surfaces like curbs varies a lot depending on car, weight, and build. Trial and error basically.

Body roll is easily modified with roll bars.

Springs are the first thing I tune. I want to get the overall stiffness of the car settled in for me first. I use the spring telemetry to get my outside tire compression to the generally the .7-.8 range for most corners. I like to go as soft as possible without feeling like I am driving a boat. Too stiff limits weight transfer which I can find to be a problem to fine tuning the car later with roll bars and dampers. So a bit of feel in how the car shifts on it’s center of gravity is involved. I also adjust my ride height generally before touching the springs. Sometimes the telemetry reads the car is stiff, .5-.6 range, but lowering the ride height can quickly reduce that range. The general advice is to lower the car as far as it will go or close, but I found on some cars that lead to the springs bottoming out regardless of how stiff I made them. On front engine rwd cars, which is mostly what I drive, I like to settle the rear end and tire spin as this stage to a large degree. So I will tend to come out of this stage with a decent bit of understeer. I then use the roll bars to fine tune overall understeer/oversteer.

Dampers are almost like black magic. I have been using some theory I found on an actual racing adjustment website.

  1. Reducing Speed (braking mostly) + Increasing Steering (Corner Entry while Braking) Weaight shifts from inside rear (Rebound) to outside front (Bump)
    = +Rear Rebound/-Front Bump = More Oversteer
    = -Rear Rebound/+Front Bump = More Understeer

  2. Decreased Braking + Increased Steering (Slow/Hard corner entry after braking) Weight shifts from inside front (Rebound) to the outside rear (Bump)
    = +Front Rebound/-Rear Bump = More Understeer
    = -Front Rebound/+Rear Bump = More Oversteer

  3. Reducing Steering + Increasing Speed (Apex to Exit) -weight shifts from outside front (Rebound) to inside rear (Bump)
    = +Front Rebound/-Rear Bump = More Understeer
    = -Front Rebound/+Rear Bump = More Oversteer

  4. Increasing Steering + Steady Speed (Sweeping Corners) -Weight Shifts from inside front/rear (Rebound) to outside front/back (Bump)
    = +Front Rebound/-Front Bump = More Understeer
    = +Rear Rebound/-Rear Bump = More Oversteer
    = -Front Rebound/+Front Bump = More Oversteer
    = -Rear Rebound/+Rear Bump = More Understeer

I tend to think of it as a ratio Front Rebound/Bump to Rear Rebound/Bump. The higher the difference between the two, the more the front or back will be pushed to the outside than the other.

  1. Reducing Steering + Steady Speed (S Curves) (Weight shifts back other direction at speed)
    = +Front Rebound/-Front Bump = More Oversteer
    = +Rear Rebound/-Rear Bump = More Understeer
    = -Front Rebound/+Front Bump = More Understeer
    = -Rear Rebound/+Rear Bump = More Oversteer
    The exact opposite of the previous. It is a bit counter intuitive, but the easiest way to figure it out is to use #4 heavily to reduce oversteer on a sweeper. If you do that, you’ll quickly find the car losing control on the second corner of an s curve. If you make your car really loose on a sweeper using dampers, suddenly it will understeer heavily on the successive corners of an S. The S curves on the Alps are a good place to see this effect.

Generally speaking, tune dampers last. Use them for fine tuning car behavior to avoid quirky handling behavior. A lot of people run high rebound/low bump (like 10 to 2). I have gone away from too low a bump as I lose braking feel in the controller. Low overall bump tends to make hitting bumps easier to handle though. High rebound with low bump keeps the car from wobbling a lot though. I have been sticking with 8-9.5 rebound with 4-5.5 bump range to keep overall stiffness up enough and keep my braking feel without getting bounced by curbs and bumps in the road. I find if I have the car pretty solid handling wise before doing dampers, I don’t feel the need to go crazy with them. the high rebound/low bump seemed to just produce odd/sometimes unpredictable handling behavior for me.

http://www.kaztechnologies.com/wp-content/uploads/2014/03/A-Guide-To-Your-Dampers-Chapter-from-FSAE-Book-by-Jim-Kasprzak.pdf
Pages 23-24

Even these two sites seem to contradict one another on corner exit. Watching telemetry would tell me forza follows the latter website more. Its still confusing to me.

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Great stuff there guys!
Keylos29 i don’t know if this made it more clear or much more complicated to me, but i love it! a lot of info to take in!

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