North Desert Dash is the considerable "sequel" to Radiator Cap Circuit.
In the cut scene, Fletcher and Gerald are fighting against El Guapo and Papo. El Guapo tells Papo the two British cars are loving his gold, which are for winning, "You cannot take first place if you do not look the part.". Fletcher asks how that'll assure him victory, and El Guapo says Fletcher has silver on his rims. They then begin a race for an unknown reason.
The race starts out on main street, and then takes a left at Glen Rio Motel/Hudson Hornet Racing Museum, next to Sarge's Compound. The race continues through a trench, and back down into the compound. Then racers cross a bridge and exit before racing behind the Radiator Cap. Then racers continue past the nature preserve and reach the courthouse, then going back onto the main road and finish line.