how do you determine the offset of a wheel (rim)
is the offset the same as the back space?
i measured the back space (5 1/2 inches)

 

you measure by looking at the drop dead center of the wheel. now if the mounting surface is going past the center, it has a positive of set. if the mouting surface is on the center, it has a zero offset. if the mounting surface is before the center of the wheel, it has a negative offset. to determine the offset, just measure how far past (+ offset) or how far back (- offset) the mounting surface is. also offset is usually measured in milimeters (mm). hope that helps

-chris

 

right.

let's say you were rolling a wheel down your driveway. Look at the centerline of the wheel (the ^'s and the .'s denote centerline)...

----
| . |
| . |
| . |
| . |
----
^
^
^

Now, the surface of the wheel that mounts to the wheel hub (on the car) is generally, on front wheel drive cars, OUTBOARD of the centerline (away from the car), meaning that you have more wheel sticking out toward the strut than you do sticking out toward the fenderwell.

This is considered POSITIVE offset. The opposite scenario is called NEGATIEV offset, which you can find on a lot of older American RWD cars.

BACKSPACING, if I'm not mistaken, is the TOTAL measurement from the wheel mounting surface to the INBOARD edge of the wheel rim, i.e from the wheel hub to the edge of the wheel nearest the strut.

Hope this helps.

Marty

 

thanks for the info (help) guys