share a photo?

 

Yeah sorry, just realised I hadn't 😅

 

Is the 7P in the background your old car👀

 

Wow you have a good eye. Nope not mine. I didn't even notice it

 

I run the same size, Speedo is now closer to accurate... Check against GPS speed, rather than showing higher speed....

 

Hi Singh, yeah I thought had seen that size used before. When check against GPS on phone it seems like the speedo is now reading low. It seemed to be bang on before, which I always thought was a bit strange. I take it there is no recalibration available? I guess as the tyres wear at least the speedo will become more accurate😁

 

But I will check with another GPS app

 

You can calculate or use any of the online calculators to see the difference and impact on Speedo as well.
From what I have gathered the Speedo is accurate now so have to stick to driving around and going through speed cameras.
I swap back to 21s so haven't bothered making adjustments to the coding

 

If you have a look under control units - dashboard 17, long coding, there should be a wheel circumference setting.
Play around with the values to fine tune your speedo calibration.

 

ok thanks. I will see someone who has a vcds

 

ok, panic over. The GPS HUD speedo app i was using on my phone is obviously out or inaccurate. Ran Google Maps on 2 phones and the speedo is still slightly below actual speed so all good. That makes more sense as the tyre calculator I used calculated only about 1% difference in circumference between OEM and the new 18's. Now to see how the tyres actually perform!

 

I'm running slightly over-sized tyres on my 2016 - using 255/55R19 instead of the OE 265/50R19 - online calculators show a 2% difference and GPS displays show speedometer to now be accurate - at least within 1 mph as neither GPS nor speedometer goes any smaller as a unit.

In the UK we get an unofficial 10% tolerance on speed limits so I'm comfortable cruising at 75 mph on the speedo in a 70 mph limit with cameras.

 

Ha, come to Australia, or at least Victoria, where we get a 2kmh tolerance at any speed. We have let the idiots take control!