I was running 15mm spacers front and rear with my stock wheel/tire and combo. I recently upgraded to 19" Champion RG5s 11.5/8 with 315/235 combo.

On a whim I tried the new wheels with 15mm spacers. The fronts were rubbing the inside wheel well plastic and the rears were sooo close to the fender I was worried I would cut the sidewall or worse....

Fast worward a few weeks and I ordered some 7mm spacers. Then on the avice of Sam at Speed Gallery i bought a 3lb mallet, masked it with duct tape and proceeded to tuck my rear fenders until they were no longer at a 90 degree angle. More like 135+ degrees. It's super smooth and even to the touch and the outside still looks absolutely flawless.

So now I'm running 15mm rear spacers and 7mm fronts on already agressive wheels and tires and the wheels are TUCKED with no rubbing! I will post pictures when I clean the car. It's been about 4 weeks since I washed that ****!

 

Here si what I calculate my offests are now. Any more in the front, and the tires will rub will rub on the inside liners.'

Champions:

19x8 46mm front – 7mm spacer = 39mm
19x11.5 44mm in the rear – 15 mm spacer = 29mm