Sorry, I meant the F24 car with the outrigger, thanks for the info. Planning to have single speed at the moment for this car since it's easier to do and more reliable. In the future, I might swap out the rear subframe to one that would allow multiple gearing to see what the difference would be which would be interesting.
Having cambered wheels (10 degrees) does improve the aerodynamics of the car, reduce drag and especially the frontal area. The front wheels with their space requirement for full steering lock means that they are widest part of the car and minimising this will also help the airflow stay attached to the surface for longer. I have tested this using different models in my flow simulation software.
One of the most efficient Shell Eco-Marathon cars ever, called PAC Car II has -8 degrees of camber, they investigated the effect that cambered wheels has on the roll resistance and found out that it doesn't add too much and 8 - 10 degrees is the sweet spot for amount of camber vs rolling resistance. If the rolling resistance was too high, they wouldn't have done it.
ETH - PAC-Car II - Aerodynamics
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