A high performance sports car (usually a ferrari, lamborghini, porsche, maserati etc...) that is bought (or rented) in order to attract women and compensate for a small penis. Also, the owner/renter has never worked on it, and sends it to a shop for modifications or repairs.
Beverly Hills is full of people and their smalldickmobiles.

Joe: Hey dude check out that guy in that new ferrari!
Bob: You mean the smalldickmobile?

A level of arrogance comes with owning a smalldickmobile

Girl: A guy in a smalldickmobile tried to make a pass at me!
Girl 2: You didn't get in?
Girl: No way! That guy doesn't have the balls to own a man's car!
by Bob Johnson-Smith June 26, 2012
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