Quote:
Originally Posted by Pintsize725
Still doesn't help me if I don't know what the heck offset is and what I should get.  |
What widths do you want? I can help once we have that down.
I can also explain...If you teach a man to fish, right?
Offsets aren't particularly hard to work with, but many people struggle because they have never had them explained well.
When you are installing a set of rims, there are generally two things you need to worry about. One is inner clearance, and the other is outer clearance.
I'm going to assume you aren't doing anything truly crazy, which means we can ignore the inner clearance and just worry about the outer clearance, which will make things a little bit easier.
Your wheel basically looks like this, with the right side being the face, and the bulge representing where the wheel mounts. The spacing between the mounting face and the center of the wheel is the offset.
If this number is zero, the mounting face is in the center of the wheel. If it is positive, it is on the face's side of center,(right, in this picture) and if it is negative, the mounting point is on half of the rim away from the face.
This basically translates to meaning a higher (positive) offset brings your wheel in tighter to the car, while a lower (or negative) offset spaces the wheel out.
To start, let's look at the stock 18" rim sizes:
F: 8" ; +43mm
R: 9" ; +15mm
So our outside width for the stock rims is:
F: = 4" - 43mm = 5.86cm
R: = 4.5" - 15mm = 9.93cm
Of course, stock rims aren't very aggressive, and most people want something that pushes them out a bit more.
25mm spacer front and rear gives us something like this:
F: = 4" - 18mm = 8.36cm
R: = 4.5" +10mm = 10.43cm
And a more aggressive 9.5/15 (this may actually rub) || 10.5/5 gives us:
F: = 4.75 - 15mm = 10.565cm
R: = 5.25 - 5mm = 12.835cm
The long and the short of this is that what offset you need is going to vary dramatically based on the width of the wheel you need, and the look you want.
Something aggressive might be in the range of:
F: 9.5" , +18
R: 10.5, +5
If you want to stay with stock widths and keep the offsets, you have those numbers. If you want to space them out more, just subtract out how much extra spacing you want* (ie, 25mm spacer takes the front to a +18 and the rear to a -10).
These numbers should give you an idea how various offsets will sit