Thanks for the replies...the NOS came with the car and all I know from the service records and work orders given to me by the previous owner is that it is the JWT system. The ECU is coded by JWT as being "555 Injectors, NOS and Federal". I don't know what shot level it is, the guy who refilled the NOS bottle asked me that as well but I don't know. The bottle is a 10lbs bottle if that says anything. It is supposed to be tied into the HKS EVC so when it hits 10psi the NOS is cut. I also have a manual cut off switch. The last owner told me it will bog like you described if the bottle is empty...