Nitro output adjustment?

[dchengtr]

Is the % how much nitrous is being released, or how much power it's giving you?

 

[atfmarko]

I think it's..the capacity of nitro tank

 

[Grayfox]

The amount of NO2 being used.

More NO2=more power, but you run out faster.
Less NO2=Less power, but lasts longer.

NO2 can not be refilled at a pitstop.