Shift light on HUD?
The fast stock guys tend to go by sound and feel on the 1-2; then steal glances at the tac on the 2-3 when it sounds ripe; and watch the tac for the 3-4. The needle and HUD shift light lag behind actual rpm due to the latency in the comms bus.
Ranger
If you use the shift light on the HUD you will definitely tag the limiter in first gear and your times will suffer.


