http://tools.ecn.purdue.edu/~krausej/rims/offsetcalc.xls

I found this on the 7thgencivic.com forum. Created by Boilermaker1.

This is for people like me who get all confused about measuring wheel fitment. All you need is rim width and offset, then just plug and chug.

*For use just as a guideline.
**Real world measurements vary by manufacturer.

For reference:
stock steelies: 5.5" width, +38 offset
flush rims: 7" width, +25 offset (taken from 5zigen Inperio)

hope this helps some people.... :wink:

EDIT:
flush rims (front): 7" width, +25 offset
flush rims (rear): 7" width, +15 offset
stock steelies: 6" width, +38 offset

u can use it as reference...but its not always accurate...

7"width offset +25 is flush in the front...the rear u can use +20 or even +15 instead

I noticed that on my echo as well.. looks like a lower offset, or wider rims are needed to bring them out in line with the fender flares.

Teddy is right.. I would even say that the offset for a 7" wide wheel should be +20 mm to be *totally* flush. There's still a little more room in the front to come out.

Peace,
m@

Hey guys.. something I've been wondering about is strut clearance. Based on the stock steelies (I figure them for 5" wide, 45 offset), how much further in can a wheel go before clearance is an issue. 5, 10, 15mm?

Here's a simpler calculator:
http://toy4two.home.mindspring.com/offset.html

Remember, if you use a different offset out back, you won't be able to rotate normally. You also need more clearance in the rear when carrying a full load.

Something else to consider is that by going with a wider stance in back, you're adding understeer which you'll probably want to counter with a larger sway bar in back or stiffer strut/spring settings in the rear.

Also, every wheel and tire is slightly different. +25 sitting flush with one wheel might be +27 in another wheel (same width). Same goes for tires fitting - just because tires are listed as the same size doesn't mean they are exactly the same. Some are very different.

For reference:
stock steelies: 5.5" width, +38 offset
flush rims: 7" width, +25 offset (taken from 5zigen Inperio)


Stock steelies are actually 15x6 ... it's stamped into the rim. But from my own crude measurements the +38 offset seems right.[/quote]

Sorry.. my estimates were based on the echo's steel wheels. Weird though.. we both run on 185/60R15 but my wheels are only 5" wide where the Scions are 6.. hmm.

Here's a simpler calculator:
http://toy4two.home.mindspring.com/offset.html


Yeah, this is way better, thanks..it calculates the clearance from stut housing too. :D

np, and I guess I need to update wheelspecs if the stockers are actually 6" wide.

How about an 8" width what would be flush lets say 17x8 what offset?

http://toy4two.home.mindspring.com/offset.html

Put 7 in the first box. 25 in the second box.
8 in the third box. you can figure out the 4th box after one try.