Tell us about yourself!
how did you put the 47k trimpot? i think the trimpot will burn if the voltage is too high
you can just jack up the rear portion of your car since your car is an RWD, jack up your rear wheels until fully hanging up then startup the engine and step on the throttle like you do on highways and watch the speedometer until it reaches 160 :D
the stepper motor you used, is it DC volts output? or AC Volts?
May I ask what car did you use? Im planning to make this circuit for my car also
Oh i forgot to read the title sorry haha