Zdc590

I was wondering if any of you guys knew what wire i should be tapping into to get the tach signal for a shift light. I've seen writeups for ls1's but obviously a 93 will probably be different and i dont feel like screwing with the wrong wire. Any help is appreciated.

sleeperLT1Z28

There is a white wire that comes from the coil and goes into a signal filter. The filter is a little black plastic box. I tapped into the wire coming out of it (also white I believe), which goes to the ecm. I use a Summit brand adjustable shift light, seems to work well.

Zdc590

Is there a wire coming directly from the tach at the back of the cluster? Could i just tap in there?

sleeperLT1Z28

I couldn't tell you that, I have not gone behind the dash. I just ran a wire from the splice through a grommet in the firewall.

Zdc590

Alright, mind telling me exactly where the plastic box is located? Thanks a lot by the way.

sleeperLT1Z28

It was sticking out of the convoluted tubing wire loom near the throttle linkage. I had to open the loom and pull it out some. It will have two white wires coming out of it. One of them will go to the coil, and the other will go to the tach. I tapped into the one going to the tach. You might want to get a Haynes service manual, as the wire diagrams are pretty good in the back.