I made this pair of front canards that fit the body lines of a 2003-2005 350Z. Not sure about later models. Keep in mind these will warp if you use black PLA - I'd suggest using ABS if possible or using white filament and painting a light color. I painted my PLA ones silver and they don't seem to warp in the tropical sun here in Hawaii. You can install them either 'lip up' or 'lip down' and I'd suggest using either rivets or stainless self tapping screws and 3M tape.
I went with 20% infill to give a nice look on the car.
Probably won't make you go faster but it sure will feel like it.