I made the biggest mistake when I first played it. Since the CSR has to be in PS3 mode to use with GIMX, it brings the PS3 mode only on-wheel settings into play. I have three presets saved on the wheel, one with 360 rotation for F1 games, one with 720 for rally games, and one with it set off so the game decides the rotation, for games like Pcars, and now AC. Well, since Pcars supports the CSR natively, which is in PC mode, the PS3 mode specific options don't do anything in that game, so I never touched them.
After playing about an hour of AC, and messing about with the FFB menu trying to find a good setup, I looked on the on-board settings, for no real reason, just messing about with them. I wondered how strong the PS3 mode's centre spring was, having not used it before, so I turned it up to max, just for a laugh. It made the wheel quite heavy, and clipped literally everything out lol, so I went in to turn it back to 0. The problem was, as I clicked down a bunch of times, it went beyond 0 into the minuses. It then dawned on me, that silly old Fanatec for no bloody reason made 0 the mid point on both the centre spring and the dampening setting for PS3 mode.
IIRC they both go to -4 and then off, so 0 is essentially 50% centre spring and dampening. I had never touched the setting, as it does nothing in PC mode, which is what all the old PS4 games used. But with F1 2016 and AC, I have to use PS3 mode with GIMX, and that brings those settings online. With it turned off, the game came alive in a big way, and now I understand why everyone raves about the FFB in AC.
Can't wait to play F1 2016 again either, because I've been playing that for ages now with those settings both at 0 lol. I just expected the FFB in the F1 game to not be fantastic anyway, so I didn't think anything of it. But with AC being so heavily praised for it's FFB, I knew something wasn't quite right. So glad I looked into it, because it should dramatically improve F1 for me now too lol.