Newbie offset ?

[red2001ss]

I'm going to run a 15x8 prostar in the rear with 3.5" BS, what offset should I get with this? Looking on Summit, the only 15x8 with a 3.5" BS they have is with a -25.00mm offset. Is this right?

 

[BlackMetal]

Offset and backspace are related, so you aren't going to find a wheel with 3.5" backspacing with various offsets.

The easier thing to say is don't worry, those wheels will fit.

 

[red2001ss]

ah, ok. So I guess those will do.

 

[BlackMetal]

Yup. Offset is the difference between the true center of the wheel (4.25") and the mounting face (where the wheel meets the hub). Backspace is the measurement of the inside lip of the wheel to the mounting face. So as you can see, if you have a certain backspacing, that's automatically going to determine where the center face is in relation to true center.

-25 offset means the mounting face is deeper into the wheel. A positive offset would be like a modern front-wheel drive wheel where the face of the wheel is almost completely to the outside.

 

[red2001ss]

Thanks.