Accelerometer implementation

[TheirOurKnowRules]

Hello,

I am using Curvy to move a slot car along the lanes of a track

I would like to implement an accelerometer to find out when the car is going around a corner too fast and have it slip off the track, but I am not getting any reading (other than gravity) when using a rigidbody, I imagine it is because I am moving the car around via a SplineController.

Could anyone point me in the right direction ? has anyone done this before? 

Thank you in advance