ok i just got a USED sportcomp monster tach(3900) and i dont got the instructions...so where does the wires go to? is this right red=ignition, grean=coil, white=light and black=ground. where would be the best place to splice these wires into?

theres also 2 small orange and 2 brown wires ... what are these for?

 

I believe http://www.autometer.com has tach install instructions.

 

red = power, you probably want to splice into a wire that is hot only when the ignition is on.

the rest you got right. just in case, for the coil, you tap the negative side, it should be a blue wire, or a blue/white wire, i forget exactly.. check a service manual with wiring diagrams.

the 2 brown 2 orange wires you cut according to how many cylinders your motor has. for 4 bangers, cut them all.

 

thanks guys but is there anyother place i can tap into for the grean so i dont have to go all the way to the coil? by the way where is the coil located on a ls motor

 

You will find the solid blue color wire on the connector attached to the distributor-that is the point to pick up the signal with the Green lead. There are other ways-but this is easiest overall. Make sure to properly insulate the connection.

 

When we installed my homiez tach, we spliced the white wire into his low-beam headlight wire, so the tach light only came on when you turned on the headlights, which would be at night. just thought that might be useful

 

You can get your coil wire(blue w/white strip) from the back of your cluster. Just take your cluster hood off and look at the wires plugged into the back side of your cluster. Splice into that wire and hook it up there easier then getting it from your engine bay.