how to recalibrate vr commodore speedo

[Kingmango]

Hey guys just wondering if there is a way to recalibrate the speedo in my vr, for when I get different size wheels and change the diff ratio.

 

[gtrboyy]

Can only be done with speedo corrector...Vdo,dakota Digital etc

 

[losh1971]

Can only be done with speedo corrector...Vdo,dakota Digital etc

^^^^^^^ this.
And don't bother with cheap Jaycar box as they don't work. Need to spend $250 - $300 on proper speedo corrector kit. I haven't bothered as I know mine is 10% out and I'm used of it and have better things to spend 300 bucks on.

 

[ephect]

You could do it with tyre profile manipulation.
I would do the diff first, then work out what rim size you want. then using a tyre size calc adjust tyre profiles to suit the % you're out by.

It's not generally done this way, but you're looking at replacing your shoes.

FYI: Law states you must keep rolling diameter within +-25mm.

 

[gtrboyy]

Heard of people putting diode in speedo wire or use potentiometer to correct it back when it seemed like a dark art.