What is it, and whats the difference between a 18x8 and 18x8.5 or even a 7.5 for that matter
tia guys!

 

18x(x) x=width of wheel in inches

don't know the offset though.. must be 35mm-ish?

 

38 mm. it's in the manual.

 

isnt the width 235, is there sevre;l ways to messure it!?

 

A quick guide

235 is the width of the tyres

8JJ 8.5JJ etc refers to the width of the rims

Offset indicates how much the rims protrude out of the body of the car.

When you go to wider rims (eg from 8JJ stock to 8.5JJ or 9JJ), you can support wider tyres (245/255 etc), you also need to get a smaller offset to accomodate the wider rims.

 

Try again /\

Offset (or backspacing) is measured from the back of the center hub contact to the inside lip of the wheel. Increase wheel offset and the wheel goes deeper into the body of the car. Decrease wheel offset and the wheel comes out from the body. If you have available inner space, you will want to increase the offset for wider wheels. If not, you usually try to stay close to the factory offset unless you need spacers to clear the calibers.

 

Thanks fellas....much better understanding now!!!

 

I know what offset is. But the best way to picture the changes in offset is to see how changing offset changes how much the rims protrude out. Maybe I should have made that more clear by indicating decreasing offset increases the protrusion, which I alluded to in my subsequent sentence.

As for wider rims, most of the rim manufacturers will recommend a smaller offset when you move u to wider rims. eg +30 on 8.5JJ from +38 on 8JJ (stock).