Its bin a while so I thought I would ask,what wire go's where?I don't know the brand name of the tac but it has a green,gray,black with red stipe and a thicker brown wire,any help would be great,thanks,,,speedfreak.

I can't tell you which wires go where, but I can tell you what some of the wires MIGHT do...

one wire will either go to the - side on coil or the tach signal on an aftermarket ignition

one might be power for a backlight feature(if the tach's of good quality).

One should be a ground

Can't think of what the fourth wire might be

_________________
My car may be slow to sixty, but at least it's been reliably slow to sixty for more than thirty years.

I thought the same,just wondering if the thick brown one go's to the coil or the one thats black with a red stripe gos to the coil,I think this tac is an external mont,you know,the type that mounts out side of the car,its all cromed metal and is heavy,thanks,,,speedfreak.

The 4 wires are usually for the following:

Trigger wire (coil negative terminal)
Ignition switched power
Dash lighting power
Ground

The trigger wire is usually green on aftermarket tachs. That is where your wire colors stop bearing any resemblance to aftermarket tachs, as the other wires are usually white, red, and black.

If I were to venture a (complete) guess, I would say

Green - trigger wire
Brown - Ignition switched power (because of heavier gauge wire)
Black w/ red - ground
Gray - Lighting

Just a guess. Hopefully someone that has used a similar tach will chime in

-S/6

I have figured it out,green-ground,gray-power for the light,black with red strip-went to the negative on the coil,thick drown-positive on the coil,every thing is working ok,still don't know the brand name,even after I opened it up,it is made in the usa though,thanks for the replies,,,speedfreak.