Rocket

You should still retard the timing even if you don't have the supercharger. Combustion is a little faster with the proper amount of nitrous so you don't have to run as much timing.

You can slowly add more timing back into the motor a degree at time and see if you are gaining more power. When you don't gain anymore power back it off the timing 1 degree. But it shouldn't need more than stock which is 16 degrees.

Tuning sounds like a pain but it gets addicting and after a while you like it. Just tweak one thing at time and use your ass as the dyno. Also you should have a buddy monitoring your air/fuel ratio when you do your tuning. You should always be running on the rich side at full throttle.

Once you feel comfortable with your tuning, you can nitrous in 3rd and 4th but I would stay away from 5th gear. Many motors have been blown nitrousing in 5th.

Aslo make sure your Nitrous bottle is warm and pointing forward. It works better that way.

You may want to try adding more fuel to the higher rpm's on the Vtec section in your VAFC.

Oh by the way, you are going to need at least 310cc injectors if you are going to run the supercharger. The stock injectors are marginally too small as is.