can you run nitrous solenoids without the relays? Can you just run a ground and and hot and then put a switch in the hot wire to activate the solenoids?

 

Yes, you could run it that way but I would recommend using a relay.

 

I have a NX wet kit in the car now and I just got the NX MAF by itself, so I can go to a dual stage. And I bought an extra fuel and N20 solenoid off a member of the forum, so the only thing I'm missing are the relays. The second stage it just going to be a "just-in-case" if you know what I mean.

Actually, can I just wire both sets of solenoids on the same relays?

 

I see. You'll need two relays to wire the two stages. You can't run 4 of the NX solenoids on a single relay because of the amp draw of the solenoids. The relays are rated at 40amps and the amp draw of each nitrous solenoid is 28 and the fuel solenoids draw 3 amps. So you have a draw of 31 amps for each stage.