Original 350z ECU - Performance Mods

[IanS16]

Hey guys (and girls)

 

I have an 02 Zed with the original (non downgrading) ECU, what are my best options for performance mods? (apart from a plenum spacerr)

 

Already have a Fujitsubo exhaust, JWT pop charger (dont think it adds any power but sounds lovely) and an increased flow Y pipe.

 

Also looking at the above is it likely that I've gained or lost any power?