Putting the transmission in neutral eliminates virtually any loss of speed due to drivetrain friction. In any case, there will be absolutely no difference in the car being FWD or RWD.
The main differences would be the rolling resistance of the tires, the aerodynamics of the body, and the mass of the vehicle.
Since RWD cars are often larger than FWD cars, they have greater frictional loss due to wide tires and a high drag co-efficient. The extra mass of a standard RWD car would only help momentum marginally.
MY14.5 VW Polo 81tsi Comfortline - Candy White - Comfort Pack
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