Calibrating VK Speedo after Diff gear change

[saladine1]

So, i'm putting in some 3.7 gears into the VK which has a VL V8 diff and standard ratio.
Gearbox is a Holden 8 T5, vehicle is sitting on 225 15x7 wheels.
What's needed to re calibrate the speedo?
If anyone has any info please let me know.

[vkberlina]

A speedo gear for the gearbox, check my site for the gear chart, might have a bit of guess work as well as some calculations to work out the right one. Although my site is for Aussie boxes the normal drive and driven gear still applies, find out how many teeth your drive gear is and work out the driven gear. Else ask in the VR-VS section they might have charts as the T5 is more relevant to them.

plus you may need to either source one from holden or drof depending on the one you need

cheers
Scott

[saladine1]

Thanks again mate.