Just picked up a HSW Interface for my dry nitrous system. Trying to sort out the wiring.

The location I decided to mount it is fairly close to the nitrous solenoid. Seemed logical and quite convenient to connect the blue interface activation wire and the ground wire to the solenoid wires. BUT... the instructions say not to connect it directly to the solenoid which means a big hassle of running wires from under the dash, probably from my window switch. Why can't we activate the interface from the solenoid power wire?

I found this diagram from Roberts Nitrous Service. My system is sort of similar to this diagram. My window switch is a dual stage Nitrous Outlet unit that has a yellow wire for the first stage trigger wire (not pink as shown in this diagram). Right now, that window switch first stage wire goes to the FPSS. So looks like I can take the window switch wire off the FPSS and connect it to the blue interface wire and then connect the brown interface wire to the FPSS. Does that look ok?



Is the window switch first stage wire positive or negative? You have to set that in the interface, so I need to know.

My other question is this: the white RPM wire is supposed to be connected to the ECM for a RPM signal. My window switch is connected to the coil pack connector for RPM. Can I connect into this same wire for the interface RPM signal too since it'll be easier for me to do? That is supposed to be optional, so maybe I'll leave it off for now?

Since I have a LS1, I will need to connect the gray IAT wire, that I know.

 

Yes 100% do not hook it up directly to the solenoid. It will no longer be your friend. Jump over to our support system and we can attach diagrams for your exact set up. The window switch wire will depend on which window switch it is, just be sure to include that information on the support ticket and the RPM wire is for top end fueling features and generally is never needed.

Thanks.

Nick

 

I appreciate the reply. Too much hassle registering and logging in to the support system.

I already have a functioning dry system. I'm just adding the interface. I will probably just connect the blue interface wire to the Nitrous Outlet window switch and the brown interface wire to the FPSS like is shown on that diagram unless I hear different.

Think I'll leave the RPM wire unhooked for now.

That just leaves one last question. Is the window switch first stage wire positive or negative? Since the 85 terminal on the relay is typically a ground, I guess that makes the blue interface wire negative then if I connect it like the diagram shows?

 

Yes the diagram is correct. Only thing you need to verify is that the dual stage window switch you are using outputs a ground. I'm 90% sure it does, but just verify with the mfg.

Nick

 

Thanks Nick, that got me on the right track. I called Nitrous Outlet and they confirmed that window switch is ground controlled. That helps a lot. Now I know how to set the interface (set the dip switch to negative).

 

What about for those of us that dont run a window switch?

 

^ what he said im running a dry hsw kit and am running just a push button.

 

There are a few ways to wire it. Easiest would be to just run a 12v through the arm switch, then through the wot switch and into the blue wire on microedge. Just make sure to open the box up and flip the switch inside to accept 12v instead of ground. Shoot me your emails and I can send a diagram.

Nick