i have a 90 bird, and the tach is out off about 20%. i know that they are notorious for it, and its not much of a problem being as a have an MSD 6 AL set at 5400 rpms, and its a automatic, but it would be nice to have a tach that was dead on. i am NOT putting an aftermarket tach inside the car, i want the interior to look original, and i hate tachs mounted inside that are as big as a clock.it looks terrible, and it is a waste of money for me. i know my tach is off, b/c when i let it hit the rev limiter, the tach starts cutting out at about 4800-5000. of its just about repairing a few simple wires, then it's worth it, however, if it's a night mare, im not touchin it.any feedback is greatly appreciated. thanx

-Tom

 

i've heard of people sending them to places like dakota digital to have them recalibrated. but they aren't just a simple fix.

if you do end up sending it somewhere, please let me know who you ended up going with. i've got an 89 IROC that i'd like to keep the original interior in as well.

 

https://www.thirdgen.org/forums/elec...meter-fix.html

That has how to fix the Camaro tach... not sure if the Firebird is that same.

 

Yea, that's the thread I was thinking of, as well.

Go to Radioshack and pick up a 100 or 500 piece variety pack of 1/4 or 1/2 watt resistors...then just use a combination of 'em to get you to around 190kish....and then after that, it's just trial and error until you get just the right resistance.

I've done this and it works.

 

or could use a potenimeter temporarily to get the correct resistance, measure it with an ohmmeter, then solder in the correct value of resistors

 

Anyone got the link or writeup to fixing the 89 and earlier tachs, mine says im shiftin at like 9 grand(guessing that since it pegs it at 7000) lmao

 

indeed, im idling at about 4k haha wayyyyy off

 

Or just leave the pot in.

 

No link to a '89 and earlier tach calibration thread?

 

I feel ya brother. I hope someone does it soon because mine is wrong and even though it's an auto it bothers me a lot. me->

 

hahaha i think i got you beat my 86 says i'm turning 6000 rpms at 20 mph in second gear. but i think i'll just put in a new gaueges and brezeal this summer (i hope)