To be honest, if you're going to build a car model, I would tell you to ditch the idea of using enamels to paint it.
I used to use enamels and to be blunt, they're smelly, slow-drying, problematic paints for car modeling. You really can't put a finger on drying time because SO many factors play into when the paint might be dry. Most good finishers will tell you that you should wait a couple of weeks, not days, to polish out a good coat. And the general rule is, if it still smells like "paint", it ain't dry. This is because the "gassing out" process of curing is still happening. Ugh. That can take forever.
The best advice I can give you is to use a good primer and go with lacquers. And WEAR A MASK! Yes, lacquers are smelly too, but they cure hard in a less than 24 hours, and polish out beautifully, and can stand more polishing abuse than enamels.