I posted this over in the wheel and tire forum with no response:

I don't get back spacing. So help me out here.

Helo Maxx 6s are 5.5" backspacing.

Stock is 5.5" correct? So that means that these would be just like stock? but 5" of backspacing would stick out about .5" further than stock?

I need some help and this is the only factor stopping me from getting the Helo Maxx 6s

 

Yes, you are correct. A wheel with 4" backspacing would stick 1.5" farther to the outside than a 5.5" stock wheel.

 

They will stick out further, because they are wider wheels.

Stockers are like 8" wide, the wheels you want should be either 10" or 12" wide.

 

Im going with a 18x9 wheel.

Stock wheels are 7.5" wide so with the same back spacing it should only make the wheel itself stick out 1.5" further than stock.

 

thumper - if you plan to go with a lift you'll have to watch as well because pro-comp and fabtech recomend 5" backspacing max

 

Here is a picture of 5" backspacing on a 18X9 wheel.

 

The width of the wheel has nothing to do with backspacing. An 8" wide wheel can have backspacing from lets say, 5.5" to 3.5". Backspacing is measured like this. Lay your wheel on the floor with the outside down(touching the floor). Next lay a straight edge across the wheel from one side to the other side, now measure from the straight edge down to the flat surface where your lug bolt holes are. This distance is the backspacing. The lower the number the closer the lug bolt holes will be to the straight edge. Which in turn makes the wheel stick further out. A 33x12.5 tire will work just fine on a 8" wide wheel. Check Tirerack.com they show the reccommended wheel width for tire size.

 

18 x 9 Rim W/6" Backspace. "stock tires"


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