The bigger the car the smaller the penis.
A small penis car is a big car driven by a man trying to overcompensate for having a small penis
Also applies to humongous "manly" vehicles that are not allowed to wear dirt, let alone get driven on it. Glossy Hummers, pinstriped pickups, and similar macho-but-impractical trucks and SUVs that cruise cities and suburbs.
The Hummer is the most useless vehicle ever built; it's the ultimate small penis car.
Derogatory word applied to a vehicle used by a guy that wishes he can afford to drive those so-called "small penis vehicles" (vehicles that seemingly are overcompensating for a guy's "under-endowment." Examples include but are not limited to: fancy sports cars, and large trucks such as F350s that are raised with a set of over-sized tires). He may also be likely doing this to make himself feel better about his small penis.
I think it's funny that poor people always dismiss men that drive nice cars by saying they must be compensating... you can apply it to any car - Mercedes? small penis car. Corvette? Small penis. F-350? Small penis... But hey, I'd be insecure if I drove a Corolla too.
Fancy-ass sports car-type vehicle. Seen driving everywhere, excessively fast, usually with loud and very bad rap or rock music blaring.
These cars are often older models, driven by young men (ages 16-30, usually).
(a white sports car with obscenely large spoiler and 50 cent's "Candy Shop" blaring drives past)
Person #1: Wow, that guy must have the smallest penis in the world.
Person #2: Yes, in fact it may even be a woman who thinks they are a man.
a exotic car such as a ferrari or a big SUV such as a hummer used to make up for having a small cock. NOT a muscle car.
*ferrari pulls up to light,revs engine* dude 1: haha,check the fag in the ferrari dude 2: he's gotta be compensating,that's a total small penis car.