o2 sensor question

can vtec kick in if you have no o2 sensor installed?? the header i have installed doesnt have a spot for it so i figured that the last person to own the car just cut it off.... i am getting a new down pipe with my turbo kit and need to have an o2 sensor for my air fuel ratio gauge to work... also can the o2 sensor affect vtec? cuz i dont belive that i feel any diff in pull threw out the rpms all pulls the same... thanks

is your motor sohc? when vtec kicks in on sohc its not really noticable, its just a longer part of the power band.

sorry i was being dumb and forgot to put up the motor... its a b16a