help tyre size
01 May 2006, 04:14 PM
#1
Scooby Regular
Thread Starter
Join Date: May 2005
Posts: 189
Likes: 0
Received 0 Likes
on
0 Posts
help tyre size
hi all
i have a 02 WRX with standard alloys currently wrapped in 215/45/17 rubber.
managed to get a cheap set of 225/45/17 rubber.
a:- will the rubber fit the alloys?
b:- togather, will it fit under my arches?
thanks
i have a 02 WRX with standard alloys currently wrapped in 215/45/17 rubber.
managed to get a cheap set of 225/45/17 rubber.
a:- will the rubber fit the alloys?
b:- togather, will it fit under my arches?
thanks
01 May 2006, 05:55 PM
#2
Scooby Regular
Join Date: Aug 2002
Location: never the same place twice
Posts: 3,346
Likes: 0
Received 0 Likes
on
0 Posts
you will have no problems with those tyres, i have the same on mine, WRX blobeye with WR1 wheels and the 225 width rubber on
although im sure you will be aware that your rolling diameter is now ever so slightly bigger so your speedo will be EVEN MORE inacurate lol
john
although im sure you will be aware that your rolling diameter is now ever so slightly bigger so your speedo will be EVEN MORE inacurate lol
john
01 May 2006, 08:24 PM
#3
Scooby Regular
Thread Starter
Join Date: May 2005
Posts: 189
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by EVOLUTION
you will have no problems with those tyres, i have the same on mine, WRX blobeye with WR1 wheels and the 225 width rubber on
although im sure you will be aware that your rolling diameter is now ever so slightly bigger so your speedo will be EVEN MORE inacurate lol
john
although im sure you will be aware that your rolling diameter is now ever so slightly bigger so your speedo will be EVEN MORE inacurate lol
john
01 May 2006, 08:50 PM
#4
Scooby Regular
Join Date: Aug 2002
Location: never the same place twice
Posts: 3,346
Likes: 0
Received 0 Likes
on
0 Posts
because the 45 bit in the tyre size is the profile.
that means the wall depth is 45% of 215mm
therefore 45% of 225mm is going to be larger, thus, making the rolling diameter bigger
john
that means the wall depth is 45% of 215mm
therefore 45% of 225mm is going to be larger, thus, making the rolling diameter bigger
john
02 May 2006, 09:04 PM
#5
Scooby Regular
Thread Starter
Join Date: May 2005
Posts: 189
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by EVOLUTION
because the 45 bit in the tyre size is the profile.
that means the wall depth is 45% of 215mm
therefore 45% of 225mm is going to be larger, thus, making the rolling diameter bigger
john
that means the wall depth is 45% of 215mm
therefore 45% of 225mm is going to be larger, thus, making the rolling diameter bigger
john
02 May 2006, 09:32 PM
#6
Scooby Regular
Join Date: Mar 2005
Posts: 3,272
Likes: 0
Received 0 Likes
on
0 Posts
You learn something new every day.
I thought the 45, 50 etc bit meant the profile was 45mm, 50mm etc.
Didn't realise it was a percentage of the width.
Scooby net is useful
I thought the 45, 50 etc bit meant the profile was 45mm, 50mm etc.
Didn't realise it was a percentage of the width.
Scooby net is useful
Originally Posted by EVOLUTION
because the 45 bit in the tyre size is the profile.
that means the wall depth is 45% of 215mm
therefore 45% of 225mm is going to be larger, thus, making the rolling diameter bigger
john
that means the wall depth is 45% of 215mm
therefore 45% of 225mm is going to be larger, thus, making the rolling diameter bigger
john
Trending Topics
02 May 2006, 11:56 PM
#8
BANNED
Join Date: Feb 2001
Posts: 624
Likes: 0
Received 0 Likes
on
0 Posts
Yes, your correct.
It's the percentage of the width.
Handy site here for working out bigger alloys / tyres.
http://www.miata.net/garage/tirecalcold.html
David
It's the percentage of the width.
Handy site here for working out bigger alloys / tyres.
http://www.miata.net/garage/tirecalcold.html
David
03 May 2006, 11:48 AM
#9
Scooby Regular
Thread Starter
Join Date: May 2005
Posts: 189
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by DR Motorsport
Yes, your correct.
It's the percentage of the width.
Handy site here for working out bigger alloys / tyres.
http://www.miata.net/garage/tirecalcold.html
David
It's the percentage of the width.
Handy site here for working out bigger alloys / tyres.
http://www.miata.net/garage/tirecalcold.html
David
Tire Size Comparison
Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
215/45-17 3.8in 12.3in 24.6in 77.3in 819 0.0%
225/45-17 4.0in 12.5in 25.0in 78.5in 808 1.4%
03 May 2006, 01:57 PM
#11
Scooby Regular
Join Date: Aug 2001
Location: Warrington
Posts: 4,554
Likes: 0
Received 0 Likes
on
0 Posts
Your tyres are bigger, therefore for each revolution you travel further, so your speedo will under-read. However your speedo is designed to over-read by +10% to -0% so it will balance the 1.4% difference.
In normal use your treads will reduce from 7mm to 2mm i.e. 5mm. The difference between 225x45% and 215 is 4.5mm, virtually the same.
ATEOTD you will not notice any difference.
In normal use your treads will reduce from 7mm to 2mm i.e. 5mm. The difference between 225x45% and 215 is 4.5mm, virtually the same.
ATEOTD you will not notice any difference.
03 May 2006, 08:06 PM
#13
Scooby Regular
Join Date: Aug 2002
Location: never the same place twice
Posts: 3,346
Likes: 0
Received 0 Likes
on
0 Posts
how do you mean under read, when im doing 30mph GPS, on the clock im reading about 36mph....
sorry if av totally got that wrong, its been a long hot day
john
sorry if av totally got that wrong, its been a long hot day
john
04 May 2006, 09:55 PM
#15
Scooby Regular
Join Date: Aug 2001
Location: Warrington
Posts: 4,554
Likes: 0
Received 0 Likes
on
0 Posts
@EVOLUTION: the tyre change alone will cause the speedo to under-read. This is balanced by the fact that they are designed to over-read as you have seen compared to GPS (true speed).
Thread
Thread Starter
Forum
Replies
Last Post
shorty87
Wheels And Tyres For Sale
0
29 September 2015 02:18 PM