speedo's out - changed diff gears

[emmtee83]

hi guys

this weekend i bought a vr stato but its dash is out by about 20km/h. i was told this was due to diff gears in.....would this be correct? and if so, what can i do to pull the speedo back into line?

thanks in advance guys

[Vee-ard]

Jarcar make a kit for this, and the majority of people who change diff gears on a street car use it.

Speedo Corrector MkII Kit - Jaycar Electronics

[emmtee83]

do you need to know what gears are in it? cos at the moment, i don't have a clue.

[Vee-ard]

well it would help, but I suppose you could see what your car does at 100.

IE: drive beside a mate on the freeway, get him to do 100, note what speed you're doing, then dial back the signal by the % difference between the two speeds?

[Verynice]

No you dont need to know the gears. Basically you calibrate it to the correct speed, such as off a GPS

[Trayner]

I need to get my self on of these too, Quick question , do you install the wire from the tranny/diff to ECU or ECU to dash ?

[hq-racing]

if its a propper diff gears change you maybe lucky and have the tag that states the gears on the diff..
if ya lucky!
other wise to sort it take it to a dyno, i did with mine when i put 3.89's in mine, re-mapped the commputer to sort.
works a treat now!