You need to set the carb jetting so the car runs well without nitrous. Then set the nitrous fuel jetting, whether its a fogger or plate system. The nitrous fuel has nothing to do with the carb jetting. With a plate it is sucked straight on through the carb to the intake. With fogger its straight into the intake runners. If you want to run a little rich for safety, alter the jets in the plate or foggers, NOT the carb.