Hooking up my monster tach. want to use the wire behind cluster instead of coil.

[houstonstangguy]

I am hooking up my monster tach and i know that the green goes to the negative side of the coil but my question is cant i just use the wire behind the cluster ? if so which wire is it? the reason i am asking is because i was back there anyway and I want to cut the wire going to my stock tach so that it doesnt work with the other tach. i just want that gauge dead. know what i mean?

which wire(s) would i use from behind my 89 cluster?

thanks guys,
joe

 

[gold73fastback]

the negative coil wire is what actually drives the tach, the other wire is simply a hot wire. people usually hook it up to the positive side of the coil because that is a keyed (only on when the key is in the ignition) hot wire.

u can use any other keyed positive wire you can find (radio, etc.)

as for disabling the stock tach, i've never been behind an 89 cluster so im not sure, however be carefull what you cut becasue it may affect something else in the circut
i assume you could try to follow it up from the coil to behind the cluster,or if u find one behind the cluster of the same color, slice some coating of it with a razorblade and check it.

example, my 88 mark VII has a bad headlight switch and the tach only works when the headlights are on

my .02

 

[houstonstangguy]

i got it. the green with yellow stripe wire was the tach wire.

thanks