i know what an offset is, but in general i dont understand the whole concept well. im going to be running an 18x7.5" rim on a 215/35/18 tire, at stock height (04 jcw) but in the future, i want to lower it, so i need something thatll work at stock height and lowered, when i do lower it.

now, the + offset and - offset....does + mean it sticks out past the wheel well more, or does + mean it is tucked more in to the wheel well?

what should i go with for my MINI for the rim/tire i posted above?

 

This might help http://www.1010tires.com/WheelOffsetCalculator.asp

 

do you know what my stock wheels are, 17x7?

 

s lite offset is +48 +50

edit: my mistake... i was thinking of the webspokes

 

They are 17x7, ET50

Think of a wheel with the hub surface right in the middle of the wheel as "0" offset. Your +50 wheels simply have the rim pushed into the wheelwells by 50mm while the hub surface stays in the same place.

Offset is easier to think of than backspacing (the distance from the hub surface to the back of the wheel) because it does not change with wheel width.

 

so with an aftermarket 18x7.5 on my mini, another member suggested me to go with a +35 to +40...is that right?

 

Well +35 should work for sure with 18x7 (depends on tire size) but will likely rub a bit with a 7.5. 40 probably handles better, and remember if you pick +40 you could always make them +35 with a 5mm spacer...

Note that camber plates and lowering can tip the tops of the wheels in too, so I'd complete any modifications before measuring for clearance.

 

so just get +40 and if need be, get the 5mm spacers to bring them in a tad? +35 is more in the wheel well than +40 is right? so being as theyre 7.5 vs 7, i should go with the +40?

 

No, a +35 is further out than +40, and spacers can only push wheels outward even more.

Think of it this way: a 7" +35 wheel is about 9/16" further out than the stock one, and a 7.5" +35 one is about 3/4" further out than stock. A 7.5" +40 is only 1/2" further out. Measure carefully!

 

hmm...so should i get a +40, and itll be 1/2" further out than stock right? if i get it the same as stock, itll be too close in, and rub correct?

 

Yep, +40 is 4/10" further out and 1/10" further in--a decent compromise. Remember when you go wider to 7.5" then the extra 1/2" has to go somewhere. If the face of the wheel were the same place as stock it would stick inwards an additional 1/2" at +63 which may rub too.

 

ya i tried to find 18x7 but i couldnt find any rim that i liked. :(

btw its the 18x7.5 Anella AN540's that i'm buying. i love how they look!