Quote Originally Posted by vwdmc16 View Post
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I wonder if you have a VSS input and GPS input to that box, which signal gets priority if the two disagree? Say if I was doing a second gear burnout but the car wasnt actually moving.
According to the Speedbox manual the GPS signal will override other signals - VSS or CAN. So, if GPS is available the speed will be taken from that. Only when GPS is not available (before satellite lock, in tunnels, etc) the speed is taken from vehicle sensors.
During a burnout with good GPS signal the speedometer will actually show zero if the car is not moving.
It seems to be a very cleverly designed piece of hardware. I like it a lot!