Offset to backspacing conversion
Backspacing is the distance from the back lip of the
rim to the mounting pad in the center of the rim, by the lug holes. This is what
you can easily measure at the swap meet, etc.
|
Offset |
6" wide rim |
7" wide rim |
7.5" wide
rim |
8" wide rim |
8.5" wide rim |
9" wide rim |
9.5" wide rim |
|
15 |
3.59 |
4.09 |
4.34 |
4.59 |
4.84 |
5.09 |
5.09 |
|
25 |
3.98 |
4.48 |
4.73 |
4.98 |
5.23 |
5.48 |
5.48 |
|
30 |
4.18 |
4.68 |
4.93 |
5.18 |
5.43 |
5.68 |
5.68 |
|
35 |
4.38 |
4.88 |
5.13 |
5.38 |
5.63 |
5.88 |
5.88 |
|
40 |
4.57 |
5.07 |
5.32 |
5.57 |
5.82 |
6.07 |
6.07 |
|
45 |
4.77 |
5.27 |
5.52 |
5.77 |
6.02 |
6.27 |
6.27 |
|
50 |
4.97 |
5.47 |
5.72 |
5.97 |
6.22 |
6.47 |
6.47 |
Stock GVR-4 wheels specs:
- 6" wide with 46 mm of offset
(see bold above).
- Bolt pattern is 4x4.5 (114.3mm), measured from center to center of adjacent
holes (not diagonal).
- Wheels are hub centric with a 67mm bore.
Backspacing to Offset
conversion
|
Wheel Width (in) |
3.25" BS |
3.5" BS |
3.75" BS |
4.0" BS |
4.25" BS |
4.5" BS |
5.0" BS |
5.25" BS |
5.5" BS |
5.75" BS |
6.0"BS |
|
5.5 |
0.00 |
6.00 |
12.00 |
19.00 |
25.00 |
32.00 |
44.00 |
52.00 |
57.00 |
63.00 |
69.00 |
|
6 |
-6.40 |
0.00 |
6.00 |
12.00 |
1.00 |
25.00 |
38.00 |
44.00 |
51.00 |
57.00 |
63.00 |
|
6.5 |
-12.00 |
-6.00 |
0.00 |
6.00 |
12.00 |
19.00 |
32.00 |
38.00 |
44.00 |
51.00 |
57.00 |
|
7 |
-19.00 |
-12.00 |
-6.00 |
0.00 |
6.00 |
12.00 |
25.00 |
32.00 |
38.00 |
44.00 |
51.00 |
|
7.5 |
-25.00 |
-19.00 |
-12.00 |
-6.00 |
0.00 |
6.00 |
19.00 |
25.00 |
32.00 |
38.00 |
44.00 |
|
8 |
-32.00 |
-25.00 |
-19.00 |
-12.00 |
-6.00 |
0.00 |
12.00 |
19.00 |
25.00 |
32.00 |
38.00 |
|
8.5 |
-38.00 |
-32.00 |
-25.00 |
-19.00 |
-12.00 |
-6.00 |
6.00 |
12.00 |
19.00 |
25.00 |
32.00 |
|
9 |
-44.00 |
-38.00 |
-32.00 |
-25.00 |
-19.00 |
-12.00 |
0.00 |
6.00 |
12.00 |
19.00 |
25.00 |
|
9.5 |
-51.00 |
-44.00 |
-38.00 |
-32.00 |
-25.00 |
-19.00 |
-6.00 |
0.00 |
6.00 |
12.00 |
19.00 |
|
10 |
-57.00 |
-51.00 |
-44.00 |
-38.00 |
-32.00 |
-25.00 |
-12.00 |
-6.00 |
0.00 |
6.00 |
12.00 |
|
10.5 |
-63.00 |
-57.00 |
-51.00 |
-44.00 |
-38.00 |
-32.00 |
-19.00 |
-12.00 |
-6.00 |
0.00 |
6.00 |
|
11 |
-69.00 |
-63.00 |
-57.00 |
-51.00 |
-44.00 |
-38.00 |
-25.00 |
-19.00 |
-12.00 |
-6.00 |
0.00 |
|
12 |
---------- |
------------ |
-69.00 |
-63.00 |
-57.00 |
-51.00 |
-38.00 |
-32.00 |
-25.00 |
-19.00 |
-6.00 |
Notes:
Important to note is that an 8" wide rim at 5" of backspacing has 12mm of
offset,the same 8" wide rim with 6" of backspacing has 38mm of offset.
The stock 6" wide rim has 46mm of offset
- A 7" wide rim should be between 35 and 40mm of offset
- A 8" wide rim should be between 30 and 35mm of offset
- A 9" wide rim should be between 25 and 30mm of offset
All of the data was compiled by Mark Rieb who is an esteemed member on GalantVR4.org.
