> There are other types of car giveaways run by more legitimate parties (charity raffles, event promotions) that do deliver the goods — but if you win, you’re liable to pay a hefty gift tax.
I don't think it's a gift tax, but ordinary income tax. A coworker won a living room sofa set on a game show, and the staff were waiting with a 1099 for her as soon as she stepped off the stage. The IRS says you need to pay tax based on the fair market value, but the shows will list the prize at it's full retail price.
So if you should happen to (and you won't) win the Acura, you'll owe 25% or more on it. Plus any state income tax. I'm not sure when the IRS actually wants their money, but a safe assumption would be "soon". Perhaps by the next quarterly estimated-tax date.