intake spacer?
 

Hey I've heard that the motordyne intake spacer makes a lot of didderence with the 350Z, would it do the same for the 370Z? If so could I use on off a dual intake 350?

I was looking into this area as well. However, based on looking at the car, I think our intake plenum is a single, solid piece. It seems to have been manufactured in 3 layers, but AFAICS there are no bolts or screws anywhere to take it apart. It must be glued/melted together at the factory. I think the only way you're going to affect intake plenum volume on our engine is to replace it wholesale.