1uz celsior autobox need cable speedo drive

**CrUZida** · 15-06-2009, 12:01 PM

As Brett said, the tab will need to be modded, or remade from scratch to suit, as the bolt spacing is slightly different. But it works.

**TurboRA28** · 20-06-2009, 07:51 PM

Worked a treat thanks all!
About 20% out but thats ok for now.

**TurboRA28** · 20-06-2009, 08:04 PM

Seeing I put the MX 83 one in and its 20% too fast.. what would suit best you think?

**brett_celicacoupe** · 22-06-2009, 10:17 AM

so the speedo is reading too fast?

youll need a drive gear off a car with smaller wheels and higher diff ratio as it should have more teeth on the driven gear.

i would try something like an RA23/28/40. then again it has a super high diff ratio right? u might need something out of a hilux??

if you know how much it over reads (exact percentage) and you know the no. of teeth on the existing driven gear then you should be able to estimate what new gear u will need

**TurboRA28** · 22-06-2009, 10:29 AM

Ahh so have to change the drive gear.. Not as simple as changing the gear on the speedo cable bit itself..

**brett_celicacoupe** · 22-06-2009, 10:37 AM

sorry i meant driven gear.

like the one in this pic. it just pulls out and you slide the next one in

**big_zop** · 22-06-2009, 10:41 AM

You may not be required to change the drive gear.

What Brett is saying is that you will need to work out the ratio and from the percentage out, it will give you a new gear ratio which you have to find the next closest available.

Say you have 33:10 gears - that gives a 3.3:1 ratio. Now its also possible to get a 3.3:1 ratio with a 66:20, though this is probably not available. There are certain gears available for a 10 tooth drive gear and you may find one that suits. Otherwise you will need to change the pair. I believe Norbies calculator has a lot of this information built into it, otherwise you may luck out with someone knowing more of the more popular speedo gears.

Takai as a few threads up on actually calculating the required gear ratio and subsequent gearset (for a W58 but the same principle applies)

**CrUZida** · 22-06-2009, 11:33 AM

FYI, auto's don't use the 30's and 10's.

They are 18:6, 19:6, 20:6, 21:6

Stock Crown autobox is to suit a 3.9 diff, so uses a 19:6 I'm pretty sure.

**big_zop** · 22-06-2009, 11:57 AM

Cheers, i was only using that for an example plus i have been doing a bit of research so that i can convert my car to manual and have a correct speedo.

And thanks for putting up the ratios, at least it shows that Joel wont have to change the drive gear.