Does your speedometer change with a change in alloys size?

1. ronaldo743 L-plater Joined: Oct 2010 Surrey Posts: 60 Saxo East Coast 1.1

   #1 21st January 2011, 17:40

   I have just got rid of my 13" wheels and purchased some 15" compomotives, how much will the speedometer be out by?
2. marcusd Saxperience Post Whore Joined: Jan 2009 warrington Posts: 7551 posi blue mk2 2003 vtr

   #2 21st January 2011, 17:58

   is a thread about it in probles section. but its not very much at all. vts come with 15'' rims as standard and saxo speedos are out anyways
3. williamanderson31 Frequent Poster Joined: Dec 2010 Bourne, Lincs/Hatfield Posts: 829 Renault Megane 1.9Dci

   #3 21st January 2011, 18:01

   just did an approx calculation - and its not rly anythin to worry about
4. Barry123 Saxperience Hardcore! Joined: Oct 2005 Aycliffe Posts: 32205 Saxo VTS

   #4 21st January 2011, 18:08

   Quote:

   Originally Posted by ronaldo743 I have just got rid of my 13" wheels and purchased some 15" compomotives, how much will the speedometer be out by?

   technically very little since the sidewall height of the tyre on the 15's will be reduced compared to that of the 13's. As a result your overall diameter and thus your rolling circumference will be roughly unchanged.
   
   Although we'll need to know the tyre sizes you had on the 13's and the ones on the 15's to be sure.
5. williamanderson31 Frequent Poster Joined: Dec 2010 Bourne, Lincs/Hatfield Posts: 829 Renault Megane 1.9Dci

   #5 21st January 2011, 18:19

   Quote:

   technically very little since the sidewall height of the tyre on the 15's will be reduced compared to that of the 13's. As a result your overall diameter and thus your rolling circumference will be roughly unchanged. Although we'll need to know the tyre sizes you had on the 13's and the ones on the 15's to be sure.

   Yeh - i was going by the wall sizes being the same - still it made very little difference
6. Rodney Established Member Joined: Aug 2010 Posts: 1778

   #6 21st January 2011, 23:29

   YES! I had 13" on my MK4 Polo and it throw it right out mate.
7. jambo18 Regular Poster Joined: Jan 2010 fife Posts: 429 gold mk2 vtr

   #7 22nd January 2011, 11:17

   It will be out but not by much mate. Just drive alongside a mate say at 50mph then look at your speedo and see how fast your speedo says your going.