MSD RPM Switch wired up need to know if done right.....

[Manewaymja2]

Hey there guys recently installed a RPM window switch to my Nitrous system. I am going to detail how i hooked it up and please let me know if its right.

RED: to Red on WOT Switch Wire
White: to Tach on MSD Ignition
Black: to Ground
Yellow: to 85 on Nitrous Relay.

See the Switch activates at 3000 RPM as it should but the WOT Switch also activates the Switch when the car is at idle (trigered by my finger on switch) so then how will this affect me when i launch and peg it to leave the line? Won't the Nitrous kick in as soon as the WOT switch is touched (RPM's are not at 3000 right away)? I am a bit confused and thought that hooking this switch up would allow me to some what by pass the WOT and only activate at 3000 RPM's

Please shed some light on this situation.
Matt

 

[faststang90]

look here at this go down to #5 shows a relay msd 8960


http://www.jegs.com/InstallationInstructions/100/121/121-8956.pdf

 

[Manewaymja2]

This diagram shows the window switch controlling the Solenoids, but i already have a WOT switch hooked up. I have seen diagrams online show how i hooked up my own but im trying to figure out if something is wrong with the way i hooked my own up.///// Anyone else. Heres the diagram i followed:

 

[Manewaymja2]

Help anyone..................

 

[Manewaymja2]

49 Views, man im i the only one out there with a MSD RPM window Switch? Like i said in the original Post its working but seems to activate with WOT switch as well so its almost as if the RPM window Switch isnt there.

 

[Manewaymja2]

Anyone

 

[RYC CUKR]

Here is how I wired mine.

Red to fused 12V positive.
Black to ground
White to tach on the MSD ignition
Yellow to one side of the WOT switch then from the other side of the WOT switch to the nitrous relay that controls the power for the nitrous solenoids.

That way both the window switch and the WOT switch have to be closed in order for the nitrous to operate.

 

[Manewaymja2]

Ok my WOT switch has one Red wire and one Black wire hooked up now. Are you saying leave them hooked up and on the thired pole on the WOT switch conect the Yellow? or remove the Black and conect the Yellow?

 

[RYC CUKR]

Right now I would imagine that your WOT switch has a hot (red) and a wire going to the nitrous solenoids (black). That way when you got WOT it powers the solenoids, which then open and sprays nitrous. Let me know if its different.

What you need to do is take the red wire off the WOT switch (the 12v hot wire most likely) and connect it to the red on the Window Switch.
Then connect the white wire from the window switch to the tach output of your MSD ignition
The Black wire from the window switch goes to ground.
Now take the yellow wire from the window switch and connect it to the WOT switch in the same spot where you removed the red wire.
Take the black wire off the WOT switch.

Since the Window switch can't take much amperage you have to use a relay to energize the nitrous solenoids.

On the WOT switch take a wire from the spot where the black wire was attached to the WOT switch to pin #86 on the relay you get to control the solenoids.


Okay from here I am going to be describing everything from the new relay you get. I'll tell you where they go on the relay and where they need to go in the car, like solenoids, WOT switch, Ground, etc.

You should have a wire attached to pin 86 on the relay coming from the WOT switch.
Now you will need a wire from pin 30 to a 12v power supply. It should be fused because it will be the power for then nitrous solenoids. I would think 20 amp should be fine.
Take a wire from pin 85 on the relay and ground it to the car's unibody
Now take a wire from pin 87 to the nitrous solenoids. You could use the black wire you took off the WOT switch earlier if it is long enough to reach from the solenoids to the relay.

If you look at figure 5 in the MSD sheet that was posted earlier in the thread yours should look similar to that except that in the yellow wire from the window switch to the relay you will have your WOT switch in line. The only wires that should be on the WOT switch are the yellow from the window switch and the other wire to the coil of the relay.