My Satsuma has this annoying wheel wobble under hard braking with grippy race tires like the Turbo III config has. I have tried to adjust the front axle for hours and hours but I can't figure out what's wrong with it. I made this new independent front suspension for the rally/race version and the wheel wobble is even worse with it. The "beamSpring" and "nodeWeight" values are similar to the suspensions of the official cars. I'd appreciate it if some suspension guru could take a look at it and tell me what's the problem. The IFS is very WIP at the moment and has no meshes yet. It should work when you put it in the satsuma210_by_mike94.zip/vehicles/satsuma210 folder.
I solved the wobbling of the IFS by changing the lower end of the shock beams from lower control arms to the lower steering axis nodes like the official cars have. The shocks also work better now with lower damping values. Sadly that fix didn't work with the beam axle. The beam axle is real PITA. I've adjusted it for dozens of hours with no success and the working IFS took only couple of hours to make. I'll try to stiffen up the axle beams and hubs in the SFA and see if it makes the difference. At least the IFS works now. Here is the latest IFS so you can test it and see if the hubs still wobble in some circumstances.
The main cause of wobble with braking or driving torque in my experience is bump or compliance steer. Check that the wheel toe angles do not change much in compression/extension of the suspension (cycling gravity a bit is a quick way to show it in the alignment debug) With beam axles, if the steering geometry is not right, the twisting of the axle under braking can cause excessive steering. Some amount is inevitable pretty much and one has to strike a balance between bump steer and brake steer by tweaking the steering arm angles. One thing that magnifies all problems is a large tire scrub radius. An example of compliance steer is when hitting a bump, the backward motion of the wheel hub causes a steering change because the path of the suspension arms and tie rod are mismatched. Its similar to the bump steer problem but looking from plan view instead of front view.
Thanks for your advice. There is about 1.5 degrees of bump steer over the whole suspension travel. I have seen some mods with as much as 8 degrees so it's not that bad. The steering linkage is similar to the T-series one and so it's pretty much impossible to get zero bump steer. The scrub radius is about 3 cm positive with default track width. I don't know how much it is in real thing, but I have read it is zero or slightly positive in old cars. I almost got rid of the wheel wobble after moving some nodes around and stiffening the hubs and the axle to the max. The wheels now turn a bit to right and left during braking instead of wobbling around like before and the axle twists a bit more causing it to "hop" few times at low speed just before stopping. Here is my new front axle for LHD version. I might update the Satsuma after some adjustments to caster, toe and SAI.
