[reggietank69]

i run a Suzuki vitara 1.6 g16a swb convertible with 31s inch iron man spring lift 2 inch body lift and custom rear frount and full siderails im trying to workout how far my speedo is out and if there is a way i can mod my speedo or speedo cable so it actualy is right b4 i loose my licence

[AckerDackerly]

(disclaimer - I have no idea what the rules/vehicle specs are in Australia, so proceed with caution...)

Two ways:

1: There "may" be an adjustment on the back of the speedometer itself (there is such an adjustment on an SJ 413 speedometer) that will allow the speedometer to be calibrated at the factory. It is NOT designed to to be used to compensate for tyre size as the adjustment has NO effect on the odometer readings - which will be off as a result of the different-from-OEM tyre size.

2: Take the Vit to a speedometer shop and have compensating gears installed to correct the speedometer AND odometer readings.

The first option is cheap but does not really work. The second option works but is not cheap. I mention the first option because it is widely publicised but not discussed in detail on the forums worldwide.

If there is a licensing/MOT issue with this, I would go for Option 2

I hope that this helps!

[alien]

Cheapest way out, if you have a smartphone, is to buy an Ebay cradle for it with a cigarette lighter power adapter to USB... then use the phone's GPS with a free app to monitor your speed.

This doesn't work if you're going for an inspection though =)

[Gwagensteve]

Your speedo is approximately 15% out, so:

85 on the speedo= 100km/h road speed
68 on the speedo= 80km/h road speed
59 on the speedo= 70km/h road speed
51 on the speedo= 60lm/h road speed

Gauge specialists can sell a ratio box for the speedo cable to get it to read right.
I use a phone app.

[Pico42]

I did the first of the two options mentioned above. Speedo still reads close to true.

Details here
http://www.offroadexpress.kiwi/Forums/v ... 23&t=25326