I finally got my 91 305 tpi running and the rpm gauge is way higher then it really is. It says that it is around 2k to 2.5k when it is really around 1k to 1.5k. Any ideas how to fix this? Or which wires to tap into to put in a separate rpm gauge.

 

Welcome to the club, my 91 reads about double too. With so many people having the same problem, I wonder if anybody has a 90-92 Camaro with a tach that works?
It appears that the problem is a bad resistor on the little circuit board inside the tach cluster. Here's the best info I've been able to find, just haven't had the time to try it on mine yet.
I'm still using the divide-by-two method!
90-92 Tach Fix

 

Great! Juuuust Great!
Now that I read this its only a matter of time that mine does not read correctly.
Thanks guys! [:@]

 

I just said a prayer for ya Mike, good luck!
Whooooops....I think with the way I worded it, it may have come out more like a hex!!!! Oh well, I tried.

 

So how hard will it be to put on an aftermarket tach?

 

Heyyyyy!
Well as long as some one does not curse me and make my junk fall off.

Aftermarket tach is simple. Power when the key is on, power for the light, ground and a signal. I think the hard thing would be is to find a place you want to put it.

 

Well...here's how the prayer went:
Dear cargods, please look over MadMikeZ28, and try to save his needle from petering out.
I dunno man, I think you might be on your own!