First things first, lowering the wheel rotation can make the FFB feel stronger. Obviously wheel rotation is all personal preference, but the lower you run it, the more you generally want to reduce the FFB effects.
Other things to keep in mind when setting up your FFB wheel for use in a Forza title.
“Force Feedback Scale” in FH4, is not an overall maximum volume for all the FFB effects. But it does impact the alignment and dynamic forces. And does not scale the spring and damper.
“Centre Spring” is a dynamic force, which basically means, it isnt always turned on. It is required in order to help with the self aligning of the wheels while in motion however.
“Wheel Damper” adds artificial weight to the wheel, as well as damping the effects of the other forces. On the Logitech G920 wheel, as well as the Thrustmaster TMX wheel; I advise this to be set to 0.
“Force Feedback Understeer” is the setting that allows the mechanical trail to show through. What I mean by this, is this setting is predominantly, what allows your wheel to self rotate when the rear of the car slides out. The higher this setting, the faster your wheel will want to rotate when you slide the rear out. Useful if you like drifting, and/or rally driving. I personally have this setting maxed, on both my G920 and my T300RS. But I like a very responsive wheel in this regard.
“Force Feedback Minimum” is the pneumatic trail effects. It allows you to feel tire grip drop off, the higher this setting is, the more noticeable and sharp that drop off is. It also adds a lot of wheel weight while driving normally. This setting will make driving on the tarmac feel absolutely brilliant, as it conveys a real feeling that the tires are gripping as the forces load up. Having this too high though, can cause major problems while driving off road. You want this setting fairly low. Enough so you can feel it, but not high enough to detract from driving on other surfaces.
The settings I use on the G920, I run at 900° on the Xbox one console. My personal preference in that regard, so my wheel settings reflect that.
Wheel settings video - https://youtu.be/xfO3lpqPyL8
G920 Fortune Island wheel/FFB testing (on road/off road/drifting + jumps) - https://youtu.be/2PPnowtdGng
If you stick with your current wheel rotation, I suggest putting your settings like this, and working from there.
FFB S 50
C Spring 50
Damper 0
Understeer 50
minimum 10
Then tweak from there. If the wheel feels too light, add a little more minimum. If the wheel doesn’t rotate fast enough for you, raise understeer a little. Only adjust 1 slider at a time, and then retest. Never change multiple sliders at the same time, as you wont know what did what.