Using an Android tablet as the brains of the car, the plan is to have it communicate with an Arduino that is hooked into all the cars key systems allowing everything to be controlled via remote control or via the touch interface of the Android.
Turning a 1978 Datsun/Nissan 280z into a future car. Inspired by Night Rider
Why don't you start with an Arduino Mega 2560 - you will need lot of io pins and will have some of them left for future expansion.