I know its how far the wheel sticks out..

But say a 40+ offset or a 45+ offset. What sticks out more and why?

I currently have wheels on my car with unknown offset and on the rear they rub the inside edge of the fender.. There 205/50/15 and the wheels are a 15x8. My car is not slammed i have fender gap, its just over bumps.


Is the offset stamped anywhere on the wheel?

 

it *should* be stamped into the back of the wheel SOMEWHERE but its not required by DOT. the higher the offset the more they will set INSIDE the fenderwell...you can try having the fenders rolled in the rear, or installing a larger bumpstop.hope it helps.

 

offset determines how the wheel is positioned within the wheel well. although offset is tied into the wheel's centerline and the plane of the mounting hub, you can really think about it in terms of wheel width in relation to the rotor on the car. a zero offset means the mounting hub and the centerline are in the same plane; hence half of the rim width is behind the rotor as in front. a positive offset means the mounting hub is away from the centerline and in the OUTER half of the rim. when mounted, more of the wheel width is behind the rotor so the wheel is actually farther away from the fender. conversely, a negative offset means the mounting hub is positioned within the inner half of the rim and thus less of the wheel width is behind the rotor (increasing chances of rubbing). you can rub along the back of the wheel well but that is usually not the case.

if you do not know the offset on your wheel, you can calculate it
- determine the wheel's centerline by diving the rim width in half
- flip the wheel on it's face. place something long and flat against the edge of the rim; do not place on the tire. from this plane, measure in towards the mounting hub. if you subtract the pervious number from this one, you get the offset (in inches more than likely). now multiply by 25.4mm to get the the format it's normally given as.

example
- rim is 8" so centerline is 4"
- from the back plane of the wheel to the mounting hub is 6"
offset is 6 minus 4, which is 2"
- 2" times 25.4mm is 50.8mm

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HamiltonRex &raquo;</TD></TR><TR><TD CLASS="quote">But say a 40+ offset or a 45+ offset. What sticks out more and why?</TD></TR></TABLE>

With positive offset wheels, the higher the number, the more the wheel moves inward from the hub's mounting surface. So a +40 offset will stick out more from the car than a +45 offset.

http://www.tirerack.com/wheels...d=101