986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - is there a fix for speedo reading too high?

boxxster · 07-24-2022, 03:14 PM

Your 17s and 18s likely have the same overall diameter which is why both cars are over-reading by the same amount. Input your tire sizes into this calculator to confirm.

https://tiresize.com/calculator/

By design, most cars over-read by some extent.

07-24-2022, 03:14 PM	#2
boxxster Registered User Join Date: Nov 2015 Location: ontario Posts: 377	Your 17s and 18s likely have the same overall diameter which is why both cars are over-reading by the same amount. Input your tire sizes into this calculator to confirm. https://tiresize.com/calculator/ By design, most cars over-read by some extent.