Question does 16/17" wheels alter gearing?

[Album56 0]

Would fitting 16" wheels on a stock G60 be an easy way of getting longer gears & how much difference does it make in practise? I have always thought 1st/2nd gears are a bit short on my G60 & I dont want to go to the bother of box out etc.

Also it might make the speedo which reads 3-4mph fast more accurate. Anybody have experience of this please.

Mick

[Kevin Bacon 5]

It's more the tyre size that affects the gearing / speedo. I've found 215/40/17 makes the speedo match the satnav exactly, instead of being 3-5mph over-reading like you say.

 

There are plenty of tyre size calculators online to see what tyre size does what to your gearing but beware going up a profile can make the tyres look like balloons!

[junkie 0]

So if it's matching the sat nav at lower speeds what is it doing alot higher up on motorways