I made all 3 cars differently, lol.
For the charger, I used a scale model and no reference pics. I started with a cube for the divider in the middle of the grille and kept extruding it.
For the corvette, I used a scale model and a side reference pic that I took with my craptacular camera. I traced the outline of the car in side pic and extruded on the x-axis, then just kept adding details.
For the gt, I'm using several reference pics because I don't have a scale model, but using the same technique as the corvette, it seems to work
. We'll see how it turns out. I'll be making a separate thread for it shortly, just need to get a little farther on it.
So, to answer your question
, I usually start with a single primitive.
coming soon: Ford GT vs. the Corvette.
No, really.
I'm serious this time.