Suspension settings

Hello,
just though I'll share some if someone is interested/have trouble/want to suggest/improve.
To go flatout in the bumps or to go anywhere at speed really at jonhson valley with the cherrier, I made this:
remove both anti roll bars (especially front)
suspension:
Front:
fast bump 2100
bump 2100
fast rebound 500
rebound 15000 (max) (more would be good for even stronger spring and bigger jumps, same for rear)
spring 71000
height max (0.06)

Rear:
FB 2000
B 1500
FR 5000
R 10000 (max)
S 46000
h max (0.06)

 

May I recommend trying KennyWahh's projekt drive suspension mod? I've made a very soft and smooth Grand Marshal config and it is better than the stock one in every way except handling (which is made up by POWER!!)

 

Great, I'll play with that. My springs were very hard but I was still bottoming out on some bumps i feel like. Just lacks some bypass shocks now.

 

There is even a "scientific" way of setting up suspensions, going from car suspension frequency to the weight of the axle and the spring strength you need for this, and the damping you need for these springs. See a gutde here: https://www.drtuned.com/tech-ramblings/2017/10/2/spring-rates-suspension-frequencies

 

I found a absorber/damper calculator here:
https://www.omnicalculator.com/phys...~:text=The formula for calculating the,√(k×m).

 

Okay, I studied the thing a bit but in beamng where we don't really have a set course we don't really take the same bumps it doesn't really matter BUT we can use your calculator so we know we have enough damping and the spring isn't going wild. I won't go into the mathematics too much because I have PTSD just thinking about it but a mass,spring,damper system follows a 2nd order differential equation (every beams in beamng works like this I believe) where we have a minimum value of the damping coeff (ξ , xi, pronounced [ksi] as I had to call it), 0.707 in the way we used to do it was the limit before the spring starts going wild but it was also the fastest recovering system. a system that is underdamped will begin oscillating in the form of a sine that is attenuating as the damping, which is too low, manages to control it.
So we want to have the critical damping coeff it will be the minimum damping we want to run. we have to choose which frequency we want to run at, I've already choosen the spring rate so it's done, I took the max spring rate I could run without being too uncontrollable. In mountain bike downhill those who wanted to do big jumps put big spring on their bike as it would provide a rising force as it would be compressed on impact giving a smooth landing. That's what I wanted, to mess around and send it to the moon.
a front corner of the rally cherrier is approx 8000 N and as P(N)=M(kg)*g(gravity in m.s^(-2) equals approx 9.8 on planet earth we will round it at 10) => P/g=M =>8000/10=800kg per corner of the rally cherrier with the 5 cylinder in it.
in the calculator I type 71kN/m my spring and 800 my weight and I get a natural frequency of 13 which is gigantic but it's fine when I go flying or through the bumps at 200kph/120mph and 11kN*s/m, fine I got 15000 on rebound (when the damper is extending) but if I lower it it starts becoming hard to control I set the fast bump(damper compressing fast) really soft as I would IRL on my dh bike the keep it plush as I know the rebound will catch the excited spring. but I will keep some (low) speed bump to control the car on braking, acceleration.

Anyway this is my way of setting up my cars for offroad, sorry for the long read.

 

i just drive my cars and adjust accordingly to the use case lol
also, you mentioned removing ARB, why is that?

 

We all do but I love tweaking things again and again so I felt like I should share my work with those who couldn't be bothered, especially with the new jonhson vally where very few cars can go in the rough.
I've chosen to completely remove arbs here because minimum stiffness is 10kN/m I believe which is already a high and I wanted an extreme setup capable of going in the bumps at high speed. ARBs connects right ang left with a spring, the more the difference of travel between L and R, the stronger the force will pull the lower wheel up and the upper wheel down, this is very good on a flat track where you want your car to corner flat to take advantage of the grip of your inside wheels and not load the exterior one too much. I digress sorry, in an offroad situation if I believe the value of the ARB at 10kN/m(meter of spring compressed) it means exactly that 10 000N (or 1000kg=1ton (just divide by 10)) of force per meter of spring compressed, this is way to much on the crawler for example you could have a meter of difference between L and R so 1 ton of force ! to make it simple, the more asymetric the roads you are going are, the less you want stiff ARBs.
I hope I answered your question, but don't believe me, do the test with and without flatout in the bumps, you have a fantastic tool for that !

 

damn i thought i thought i knew how to tune cars, but you are taking it to the next level

 

This is just the theory, real suspension engineers put that into equations and it's not fun at all, also I'm not that capable. I just manage to make stuff handle. btw I managed to pull 1.55 g with the old pessima the other day if someone is interested.