speedo way to fast

Hi I would like some help with my 86 cabby, the problem is that at 30 mph my speedo reads 50mph and as i go faster so does the speedo, at 70-mph its reads well over 120mph.  

Sounds like your speedo is in km/h not mph.

i had an astra sri like that! but sorry dont know what the problem was!  i got the needle right round on the m way!! prob doin about 110 tho!

Have you got the right speedo drive fitted? There's two different colours - grey & red, I can't remember which is the right one though  

Harry the B#stard said

Have you got the right speedo drive fitted? There's two different colours - grey & red, I can't remember which is the right one though  

The speedo cog only corrects about 10% variation though. He has 60% variation, and by sheer chance 1mph = 1.6km/h. Its too much of a chance, and too far out, not to suspect this instead. Possibly there's something going on like this car is an import and has a km/h only dash, etc etc.

The speedo does exactly the same on my cab - It's not an import and I'm pretty sure the dash hasn't been messed around with. A friend of mine who cut his teeth on Mk1's with VW back in the day, told me to check the drive first, if this isn't the fault, it could be the clocks themselves - something to do with mechanical resistor in the speedo itself  :dontknow:

cheers guys.

just get another instrument panel and get a reputable garage to change it and give you a certificate stating the original and correct mileage on the car and that of the replacement clocks. this way you and any future owner can work out the original mileage....if your that bothered!

open the clocks up and tighten the spring that returns the neddle - trial and error
or take it somewhare to get it calibrated

wheel tyre/size????

still on the original wheels size, not that bothered about it but it is just a little annoying that i am clocking up extra mile when i shouldnt be.
Going to change the cable first but have a new clock standing by just in case..