Best way to get speedo working right?

[haydenz]

I have been really lazy and havent really asked this question, I have changed the whole running gear in my car to JDM, and the only thing that broke was the speedo cable. I put my ADM one back in and the speedo is up the shit, (wobbles at slow speeds, Its about 10km/h under the actual speed). Whats the best option? Should I just buy a new JDM one or is there a converter that you can buy?

Would a gearbox shop be able to fix this problem??

Cheers

[ke70dave]

just to clarify,

you had a adm sponntah, with a t50 box and a set of wheels on it.

and you changed only the gearbox and nothing else (in the drivetrain)?, and your getting funny readings from your speado cable?

you haven't changed your diff ratio at all? or you haven't put different sized tyres on the back?

the fact that the speedo is jumping around at low speeds, suggests to me that the speedo cable isnt in the best shape, but a speedo cable is just that. its a cable that spins, i would have thought it either spun or it didn't (ie a broken cable, in which case the speedo should do nothing at all).

unless the end that goes into your dash is slightly bent or something? and gets caught at low speeds?

one thing you could try, is putting the speedo gearing from your old gearbox (if you still have it) into the new gearbox?

im of the understanding you can interchange the little connection that goes into the gearbox. though i myself have not done it.

jsut an extra thought, dont jap 86's come with 14" wheels? and adm come with 13? could that account for the difference in speed? (+/-10km/h or so). in which case changing the cable gearing as suggested above should do the trick...

[Skylar]

the OD of tire is still the same whether it's 13" or 14".

Take the cable out and degrease the thing.

It's "10km/h out" because it most likely has a 4.3 speedo drive gear and a 3.9 diff.

[ae86]

hayden what profile tyres u got on ur 15s ? may also be ur cw&p ratio, standard jdm ones are 4.3?

[ke_70]

the OD of tire is still the same whether it's 13" or 14".

?????? that makes no sence at all

[Skylar]

Haha, I guess it doesn't.

You know what I mean. 155/80R13 is same as 185/60R14 which is same as 195/50R15

[haydenz]

Yea I think it may be the speedo cable, I swapped the rear end to JDM discs (not sure if its zenki or kouki) and the gearbox is also a jdm box. The cable that was put in was shagged, so I swapped it with my adm cable...but I still had the same problem.

I am running 15 x 195 x 50 tyres so I know that would be a factor aswell.

I did hear there is 2 more teeth on a JDM speedo cable than a ADM one???? Not sure if anyone can clarify

[Rice86]

haha i had this same problem....as soon as i took the speedo cable off from the gearbox and put it back in.....was jumping at 10kmph on the dash but after 30-40kmph it would be normal...

try to reposition the angel the speedo cable is connected to the gearbox, try to make the cable inside spin more freely... sounds stupid and useless but i was able to get it to work correctly after 5kmph on the dash... simple but effective for my situation anyways haha