I bypassed the old junk cruise control(didnt even have the stalk for it or wiring before I got it) and finally put in a new speedo cable. Well it works but the speedo is reading about double the right speed. It says I am doing 80 in third gear(which is impossible). I dont really know where to start on fixing this and the search didnt find anything but a speedos 10 miles off. I have an 83 firebird, 5 speed trans.

 

Welcome to TGO. Start with the following link:

https://www.thirdgen.org/forums/inte...eedo-woes.html

JamesC

 

I already tried that link. I went through a few pages of searches and a bunch of different search terms but didnt find anything like what I have. Could the speedo be bad? I have 15 inch tires on it(someone swapped the doors,seats, and wheels from a camaro) but I doubt that would cause the speedo to be off by that much. Oh well, I guess at some point the trans was swapped and the speedo gear is wrong, its about all I can figure happened(probably swapped for one out of the camaro).

 

You probably need to drop the diff cover and verify what the gear ratio is, then take a peek at the drive/driven gears in the trans to establish that they're correct for that rear.

https://www.thirdgen.org/forums/tran...-10-bolts.html

If all that's as it should be, the conclusion, since you have a new cable, is that the speedo head is malfunctioning.

JamesC

 

When you say speedo head, is it the speedometer itself that you look at in the cluster?

 

Yes.

JamesC