me and my friend are installing a mallory 685 and we want to use it as a rpm window switch as well as just the timing retard feature... i changed a diagram to what we need... i just wanted to make sure i hook up all the wires up right... we want the box to only retard timing inside the rpm window AND only when the wot switch is activated... can anyone tell me if this is correct.... oH and where does the inline fuse go... there are 2 dif spots i made cuz i wasnt sure...

 

my friend wired mine up for me EXACTLY how you want it. the retard only activates when the solenoids open and that is only when it is in the proper window and at WOT. unfortunately i dont know exactly how he did it, he didnt relaly go off a wiring diagram, but ill have him take a look at yours and let u know. i know for sure tho its possible, i just dont know jack about wiring so ill have to ask him for ya.

 

I have a drawing laying in my shop of how I did it. I wired mine up exactly how you did. Except I don't have a fuse between the arming switch and the WOT switch. But where you have the other fuse is correct.

 

cool... can you tell me if it is correct for retarding timing when the wot and the arming switches are activated?

 

yes that is the correct wiring....you just don't need the fuse on the wire from the arming switch to the WOT switch

 

Thanks guys

 

Wouldn't it be easier to just add the yellow wire (from the Mallory 685) to the violet wire that is going to the fuel pump safety switch?

 

the yellow wire is reading 12v
the violet wire is ground

 

The yellow wire will only read the 12volts when the violet wire goes to ground inside the Mallory box (window switch active) and all other switchs close. The violet wire will be 12volts when the WOT closes and the FPSS switch closes and the RPM window switch closes.

 

The fuse is needed but should be installed before the switch. Without a fuse protecting this circuit if the switch were to short to ground internally (fail) overheating and possibly a fire could result.

 

The switched 12v source being pulled from the vehicle will/should have a fuse.
The 12v constant in the diagram has a fuse on it.

What I was saying is the fuse between the arming switch and the WOT switch is redundant