I got a D16Y7 (stock), and I've heard good things about the Y8 intake manifold. Is the Y8 head better then the Y7 as well? Basically,

1) what makes the Y8 intake manifold better then the Y7?
2) is the Y8 head better then the Y7 head? would it be worth the $$ to swap it?

the car is mainly a street driven commuter, but I am thinking about trying autocross this summer....besides a little more power is never a bad thing.