Welcome to the North American Subaru Impreza Owners Club Friday September 19, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
Click here to visit TireRack
Tire & Wheel Forum sponsored by The Tire Rack

Losing traction? Need new tires?
Click here to visit the NASIOC Upgrade Garage...
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Tire & Wheel

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 06-10-2009, 02:12 PM   #1
gingburg
Scooby Newbie
 
Member#: 195039
Join Date: Nov 2008
Default 08 Impreza 2.5i 4dr tire size

So I just got the 07 WRX oem 17x7 wheels and I am awaiting installation, I assume they will fit fine on my 08 2.5i - correct me if I am wrong. But I was wondering what people thought of tire size. Will I be okay with 225/45/17 or do I need to go smaller. Everything is stock except I have pinks (springs), and sway bars (aftermarket). Thanks guys, ps i don't know anything about this stuff. Thank's.
* Registered users of the site do not see these ads.
gingburg is offline   Reply With Quote
Old 06-12-2009, 07:50 AM   #2
MYfirst00
Scooby Specialist
 
Member#: 22928
Join Date: Aug 2002
Chapter/Region: NESIC
Location: Fitchburg, MA
Vehicle:
2011 WRX
Satin White Pearl

Default

You'll be fine with 225s.
MYfirst00 is offline   Reply With Quote
Old 06-12-2009, 11:36 AM   #3
gingburg
Scooby Newbie
 
Member#: 195039
Join Date: Nov 2008
Default

Some people say that it will mess up the speedometer, or the suspension is not correct for this size. Any explanation. Thanks
gingburg is offline   Reply With Quote
Old 06-12-2009, 11:48 AM   #4
MYfirst00
Scooby Specialist
 
Member#: 22928
Join Date: Aug 2002
Chapter/Region: NESIC
Location: Fitchburg, MA
Vehicle:
2011 WRX
Satin White Pearl

Default

Quote:
Originally Posted by gingburg View Post
Some people say that it will mess up the speedometer, or the suspension is not correct for this size. Any explanation. Thanks
The only way you'd see a difference in your speedo is if you're going about 500 miles per hour. At any speed you're capable of with the car, whatever fraction in the sidewall height from stock is not going to be noticeable. I've had 215/50-17 on my Legacy (stock is 205/55-16) and there was no difference in my GPS calculated speed and my speedo. Your struts would be the same as a WRX, so you have the same amount of room within the perch height. And they run 205/50-17. 205/50 sidewall height it 102.5mm, and 225/45 sidewall height is 101.25mm. That's a difference of 1.25mm in height - hence no noticeable difference in speedo calculation. The difference in tread width at the top is 20mm, or 3/4". So the fact that your 225mm is sitting lower at the perch level is still well within spec since the perch gets wider as it goes lower to the strut.

Ryan
MYfirst00 is offline   Reply With Quote
Old 06-12-2009, 03:20 PM   #5
gingburg
Scooby Newbie
 
Member#: 195039
Join Date: Nov 2008
Default

so does the lower perch refer to the lowering springs the pinks, thank you for all your help.
gingburg is offline   Reply With Quote
Old 06-12-2009, 03:26 PM   #6
MYfirst00
Scooby Specialist
 
Member#: 22928
Join Date: Aug 2002
Chapter/Region: NESIC
Location: Fitchburg, MA
Vehicle:
2011 WRX
Satin White Pearl

Default

The perch is the bottom cup of the strut that the springs sit on. Looks like a funnel. When you stick your finger at the inside top of the tire, that's where the perch is.
MYfirst00 is offline   Reply With Quote
Old 06-13-2009, 11:01 AM   #7
aba4430
Scooby Newbie
 
Member#: 211632
Join Date: May 2009
Location: Pace, FL
Vehicle:
2008 Impreza OBS
Ob black/DGM

Post

At an indicated 65 mph on 205/55/16 stock tires, you will be actually driving 65.25 mph on 225/45/17 tires, hardly a difference to be worried about. Is a 7" width wheel specidified for use with a 225 wide tire, make sure of this. I have not checked. Use this link to play around with various scenarios:

http://www.discounttiredirect.com/di...foTireMath.jsp
aba4430 is offline   Reply With Quote
Old 06-13-2009, 02:00 PM   #8
mosc
Scooby Specialist
 
Member#: 177401
Join Date: Apr 2008
Chapter/Region: Tri-State
Location: Philly
Vehicle:
2004 STi White
16G powered lagless fun

Default

Spedo difference is misleading. Tires generally have about 11/32 of treadwear top and bottom. The difference between a worn tire and a new tire can be over a half an inch of overall diameter (~2% different than stock). Obviously there's some margin there anyway so don't sweat it. Within 2% is fine.
mosc is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Will a Catback for an 08 WRX fit on an 08 Impreza 2.5i? StickyBrokeConfused Newbies & FAQs 5 12-05-2013 11:33 AM
Michelin Primacy tires on 08 Impreza 2.5i Old_Lady_Driver Tire & Wheel 2 02-28-2010 12:45 PM
Wheel and tires fit on 08 Impreza 2.5i PP juny102004 Tire & Wheel 5 05-10-2009 05:59 PM
08 Impreza 2.5i or 08 SI? jtom12 Impreza Forum 8 02-05-2008 06:03 PM
08 Impreza 2.5i ? 240c Normally Aspirated Powertrain 106 01-11-2008 02:10 PM


All times are GMT -4. The time now is 09:07 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.