My tacho reads very high at idle it sits at about 3500 and at a medium to full rev the needle is hard against the stop. I have replaced the complete cluster and I have replaced the distributor I have also checked the wiring between the distributor and the tacho WHAT more can I look at?

 

more than likely your tachs are no good, I've had the same problem. apparently someone figured out how to fix it by soldering in a resistor

 

thanks redfire, I might try fixing my old tach as parts for camaro's are a bit hard to get in New Zealand

 

https://www.thirdgen.org/forums/elec....html?posted=1

see that thread. ive done this now to 2 cars, and both work fine. I highly recommend it.. It is simple 2 100k resisters at Radio shack is what i got.. cant beat it.. cost me all of 99 cents to do 2 of them.