For those of you that have used it, how did you install and set it up?

Off a coil pack set for "coil-per-cylinder" or off the ECU feed line set for 6 cylinder? I would assume off a coil would be easier, cause then you wouldn't have to deal with running wires through the firewall.

Also, once I install the switch, where do I wire the output (ground) to? Do I have to add an extra relay to the NOS circut to make this work?

Thanks!

 

Are you installing this inside the cabin or out? I was under the IMPRESSION (read: assumption) that you could snag the feed off the line that feed the Tach. Or is "ECU feed line" tech talk for tach feed?

 

Not sure yet. I think the ECU get the same signal as the tach, and that would be easier to get to. So if I were to do it inside the car, I'd just get the signal from there. However, I think people who are using them (and the Harlen RPM switch for the VI's) are putting them under the hood and getting the signal from a coil.

 

Got it....then at this point, I am of no use to you...sorry

 

For my MSD window switch I tapped into one of the front bank coils for the tach signal...I believe I tapped into the white wire? I'd have to look to be sure.

 

How did you wire the output from the window switch? I assume I have to add another relay to the picture, correct?

 

ok...I'll clarify what I did...becuase I went a took a look at it. The Tach signal wire is tapped into the green wire with a red stripe on one of the ignition coils.
The output from the window swith is wired to the Nitrous relay ground. This will provide ground for the relay and subsequently turn the Nitrous on and off.

hope this helps!

 

Ah, that does clear things up. Thank you!

 

no prob....good luck!

 

It will work without a relay. The solenoids aren't drawing that much power. I did add a relay eventually.

 

Can I get some directions on how to add a relay. I have one but I have no confidence in my electrical skills.

 

I don't remember all the terminals. I followed a diagram from somewhere. I'll try to dig it up.

 

Hey guys -

I'm just now getting to installing the NOS kit, and the window switch is still confusing me. Brian - You said to wire the output of the switch to the ground of the relay, but the ground on the relay is going to the solenoids...



My thinking right now is that I wire the output of the window switch to the ground of the first solenoid...so it won't function until the specified RPM's are reached.

Or, do it go to the ground on the arming switch, turning the entire system on and off as you stated?

Thanks!

 

Umm, with a Harlen use a relay because the solinoids are drawing enough amps to fry the window switch.

Unless you bought the sealed version of the Harlen switch it should not be mounted under the hood.

 

Okay, what should the relay control? Power to the main NOS relay?

 

It should be the ground for the main nitrous relay.

I have 12v going into my relay's switching curcut, then the ground out of the relay set up like this in series. WOT switch->In Cabin Activation Switch->Window Switch

 

I'm affraid that I don't know what you mean. Which relay are you refering to as "my" relay.

Also, according to the NOS diagram, the incabin switch and WOT switch get connected to the main NOS relay...does that remain the same?

 

using the diagram wire it into the wire comming from the wot switch, it becomes the ground.

 

Final question, I hope!

I'm still confused as to how to wire the window switch to the relay to make a gound...I've only used them for power.

Thanks again for your help. I apperciate it!

 

Relays make my head hurt....I can't help ya because I don't know exactly what you're asking...

 

My (basic) understanding of relays is this...

There are 4 connections...

1. 12v source to be "relayed"
2. Ground
3. Activation
4. Output

So how do you wire a relay to provide a ground to the WOT switch as Matt suggested?

 

I wish I could be more specific..... if it is anything like the RPM switch, you will have a switched ground which will activate the switch at your set RPM's.

For instance, my RPM switch has a switched ground running to the vacuum solenoid which activates the Vi. At the set RPM, the switch is activated and the switched ground from the RPM switch completes the circuit via the solenoid.

It sounds like the Window switch would do the same thing. At your two set points, the ground is activated and turns your nitrous on and off so you spray only between these parameters.

You may want to check some of the VI threads as the logic is similar.

I was pretty confused when I first did it.

D

 

I've done that...this is the best explination I could find:

This makes sense to me, if you were going to use the secondary relay to provide the main power to the main NOS relay...however, its been suggested that I use the window switch in conjunction with a relay to provide the ground...which I don't get.

 

I have the MSD window switch and the only relay in my set-up is the main nitrous relay. I've been trying to picture how you would wire and another relay in conjunction to the rpm switch...and I can't figure it out. I'm horrible with wiring and electronics. Sorry

 

Okay...will this work:

Add a second relay.

-Supply to the relay is the 12v from the battery
-Switch to the relay is the activation switch from the main NOS switch
-Output goes to the orange wire (supply) on the NOS relay
-Ground is the Window switch

Which, if I'm not a moron, would mean the the entire NOS system would only get power when the window switch grounds, meaning its in the correct RPM range.

Does that make sense? Will that fry the Window switch. It sounds a LOT like what the VI guys are doing.

 

This is what I'm thinking:



-The blue box is a second relay.
-The green box is the window switch.
-First orange line is input from the battery
-Black line is ground from the window switch
-Red line is activation from the NOS switch
-Second orange line is output to the main NOS relay

Just wanna make sure I won't fry anything.

 

However, looking at this...I think I understand what Matt was saying. If I can ground a second relay with the window switch, just use it as the ground from the WOT switch and it will ground the main relay.

It shouldn't matter, right?

 

BINGO!

 

Thanks for the help! I just had to work it all out in my own head.