FIND THE CEILING. THEN LOOK FOR THE GLOW.
Top speed is easy to describe and surprisingly easy to miss. A number in a sidebar is not much of a lesson while the track is moving underneath you.

Driver School now lets the car earn the moment on a straight. Arthur waits until the racer is genuinely pinned at the ceiling, then slows the race just enough to point at the two tells: the full speedometer and the glow around the wheels.
First he says what to do — keep accelerating on the straight. Then he names what happened — glowing wheels mean you have reached Top Speed, and that is the limit. The Gear Shift card arrives after the player has seen the old ceiling for themselves.
The track, handling model and card effects are unchanged. This is just a clearer handoff between driving fast and knowing why the car has stopped climbing.