green wire will go to my tach
black wire will go to any ground ground

those I know for sure...now for the ones I'm not sure.

red wire will go to a switched 12v? like could I splice it into my arming switch?

and the white wire will go to the ground of the relay?? does that replace the ground from the relay, as in I take the ground already on the relay out and replace it with just the white wire from the window switch? And how does that diode fit in?

 

Can somebody give me some advice? I'm going to be doing the install today after work.

 

anybody?? I only have two hours left before I go and start my trial and error routine.

 

Yes the white wire will be the new ground for the low current side of your noid relay. Also I would suggest hooking the red wire to a switched (as in key) 12v source, the reason why is if you want to use your arming switch as an on button (example: you are flooring it with the system off and want to turn it on) the switch takes a few seconds to start working.

 

Well this is what I did but I have not yet checked to see if it works.
I hooked the green to the tack, the red to a switched 12v source, the black to a ground, and...

the white to the ground of my wot switch, and no use of the diode. Will that work? as in when the rpms are within my range, it will give the wot switch ground and start to spray as long as the nos is armed??

 

Well this is what I did but I have not yet checked to see if it works.
I hooked the green to the tack, the red to a switched 12v source, the black to a ground, and...

the white to the ground of my wot switch, and no use of the diode. Will that work? as in when the rpms are within my range, it will give the wot switch ground and start to spray as long as the nos is armed??

 

Yes that will work, you can get relays with diodes built in, radio shack or any auto parts store should have them. The diodes are to filter electrical "noise" that can cause problems with the window switch. You might as well use it.

 

So even though I have the white wire going to the wot switch, I can still have have problems without using the diode? Am I suppose to hook up the diode even though I have nothing connected to the relay from the window switch?

 

Are you saying the WOT switch is between the relay and the window switch? I would still just get a diode relay.

 

The window switch grounds the wot switch. the other wire that goes to the wot switch goes to the relay.

 

You should be fine try it and if it has problems just go buy a diode relay and put it in. Have you used it yet?

 

Man....I'm selling my harlan window switch. It sounds like to much trouble too hook up.

 

Its the same to hook up as any other window switch. The only thing is that it takes longer to change rpm settings.

 

Yeah, it wasn't hard at all to hook up, I just didn't understand how it operated so I was confused on how to hook it up so I wouldn't sell it if I were you. I just had to realize it just throws the ground at certain rpms. I haven't used it yet because I have no nitrous. But I took the ground off of the wot switch and cliped a test light to it. Held the needle to a 12v source and went for a drive. Everytime I hit the min rpm the light came on so I know it's working. Didn't test the upper rpm but I assume it's working.