Help understanding offsets / outside tire location

Hi All,

I am a big newbie when it comes to understanding offsets etc.

I would like to be able to estimate how much more or less a tire would stick out given wheel width, offset, tire section width, etc.

For example:

On my X5, I have Y spoke 214 wheels that in front are 20 x 10 ET40 running stock 275/40. In back they are 20 x 11 ET 37 running 315/35.

If I was to run a square set up without spacers and put the 20x10 ET40 with 275/40 on the back, how many cm/mm of difference would I see relative to where the outside edge of the tire was with the 20x11 ET 37.

I would like to understand how to calculate this so I can do it for other configurations. I assume this is also how one calculates which size spacers one might want to use.

Can someone point to a good tutorial, web app/calculator etc.?

Many thanks.

http://www.rimsntires.com/specs.jsp

Originally Posted by djsaad1

http://www.rimsntires.com/specs.jsp

Thanks for posting.

Unless I am not understanding it though, it doesn't give me the difference in the where the front face of the wheel/tire is going to be. It only tells me if the wheel will clear in back. It looks like there paid version may help, but I don't really want to pay for a wheel app.

Anyway else have an internet tool they use?

Originally Posted by dnadrifter

Thanks for posting.

Unless I am not understanding it though, it doesn't give me the difference in the where the front face of the wheel/tire is going to be. It only tells me if the wheel will clear in back. It looks like there paid version may help, but I don't really want to pay for a wheel app.

Anyway else have an internet tool they use?

The bottom part shows you how far away or how close the tire will be to the suspension and/or fender.