F1 2015 Steering linearity

[ichu26]

I've got a problem with my steering wheel, it's Speedlink GT Carbon or something like that, it's not supported wheel so I haven't got advanced wheel settings and I can't change linearity. My question: Is it any way to change this value in some game files or any other way? I really want to play, but playing on Xbox360 controller is terrible, even the cheapest wheel is better than this. It's sad, because this wheel used to work in previous F1 games and I could change every single value. Sorry for possible mistakes, English isn't my native language.