This is impressive, it really captures the speed factor and the handling feels so nice, I will surely keep an eye on this project.
Just for the record, I know this was meant to be played with an Xbox Controller but I only have a DualShock4 so I played it that way and discovered something because of a funny accident: the A button and Steering are both linked to the left stick, so I had the precision in both steering and acceleration (I guess you used Input.GetAxis instead of GetAxisRaw?) and that allowed me to take the turns better and with less loss in speed. Hopefully I explained that right.
My recommendation for future iterations would be to change the acceleration from the A button to the RT (or some other ranged input) or maybe allow a remap in the settings menu to let the players choose their preferred way of playing.
Keep it up! You have a great project in your hands :)