entirely. The "patina car" is a correct term. Please google the images.
Patina car is any car with the emphasis on the outter exterior being faded, rusted, etc etc.
The emphasis is on the body, note the engine is not usually important for the looks of the vehicle.

The Rat Rod is usually more of a lowered 1930 era car also with worn out, rusted, look, but it also is showing off a Rat Rod engine.
You have to show off the crazy blown engine on a Rat Rod.