If the kid or one of his buddies is hooning in it and gets killed or maimed, he will never, ever be able to live with himself. If it's his only child, he'll probably eat a bullet.
Think I'm being dramatic? It happens
nearly every freaking day here in SoCal, a massive collection of fun cars, people and twisty roads. I'm sorry but anyone who would give a 16 y.o. a powerful sporty car is a freaking idiot. I got in lots of trouble with slow cars in HS, drinking and driving was simply the norm as was fist fighting and trying to get girls naked.
Did parents witness any of this? Of course not. Everyone thinks that their kid is "responsible", (well, maybe not everyone). If his balls have dropped, there is a good chance that he's a normal teenager looking for some fun. Talk your dumb friend out of it. He's not thinking straight.