Okay let's start here.
1. NA injectors are 460cc & Turbo II injectors are 550 so yes the are upgrades. You will need to increase the fuel to achieve power levels near your goal.
2. I would suggest doing the ECU & fuel upgrades at the same time.
3. Looking for a "CAI" well click the link.
http://www.corksport.com/86-91-rx7/f...haust-systems/