A couple of nitrous questions?

go to the nos webpage on their tech section there is scads of info there on jetting.

as far as the NX kit is concerned the book that came with his kit has all of the jet sizes listed.

the problem in both situations is lack of an adequate fuel system to handle more nitrous without leaning out the mixture excessively. in both cases just contact the manufacturer for their recommendations on upgrading the fuel system and you should be golden.

FYI just tossing in the next bigger jet is not a good idea = melted motor.

Then really all you need to do is call up the respective manufacturer and ask for their tech guy. They can direct you as to what their solenoids will flow etc. I sell NX systems and the solenoids that come with them will definitely out flow the 150 pills that come with the kits. The nozzle and its atomization and freeze up properties may come into play however. I am not super familiar with th NOS nozzles but I know that NX sell a SHO nozzle that is good up to 400 hp so that may be the next step for both of you really. Upgrading the nozzle will allow you to use whatever you are adding by way of squeeze. Keep in mine that fuel alone wont protect you. At the levels you are wanting to run the cyl. pressures and detonation become critical. An aftermarket ignition and good head gaskets and head studs may be required, maybe even o ringed heads and block. the best advice will come from the manufacturer of the kit. Hope this helps