So I was wondering if anyone knows any other tricks to get some more hp?
I got a 04 motor with a catless y pipe, a pop charger and I'm ordering a 5/16 ISO thermal plenum spacer soon ? Anyone know any other mods?

 

You wont get much NA.

Either go FI or prepare to go FI.
That money you have planned to spend on mods, save it to build/drop built engine into car.

Also.

https://my350z.com/forum/na-builds-498/

 

As said above: if you want to make power, you're looking at FI.

 

https://my350z.com/forum/na-builds-498/ is a good place to start.