Can I run these on my 72GS?

Discussion in 'The Hides' started by duke350, Feb 1, 2016.

  1. duke350

    duke350 Well-Known Member

    18x8 front (255/40/18) and 18x9 rear (275/40/18). They are black Foose legend wheels. Anyone see any fitment issues with this wheel package?
     
  2. pro tour gsx

    pro tour gsx pro tour gsx

    those widths will fit no problem, you just have to get the rite backspace.
     
  3. duke350

    duke350 Well-Known Member

    Right on man, thanks for letting me know. I don't know what the back spacing is. Front says offset 1mm and rear says offset 7mm. Is this what you mean?
     
  4. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    No, offset is the distance from the center of the wheel to the mounting face. There is - and + offset.


    http://www.tirerack.com/wheels/tech/techpage.jsp?techid=101


    Back space is the distance from the back side of the rim to the mounting face.

    https://www.youtube.com/watch?v=n96lE8jdMlQ

    Back space is far easier to measure. You can figure out back space from offset, but you need to know whether that offset is + or -.


    There is 25.4 mm in 1", so we are talking very small distances at 1 and 7 mm. For all intents and purposes, in this case, it looks as though the back spacing is at the center of each wheel as offset is very minimal, and we don't know whether it is + or - offset. The center of an 8" wide rim is 4", so back space on that 8" rim has to be about 4", optimal back space on an 8" rim is 4 1/2" for the 70-72 GS. On the 9" wide rim, the center of the rim would be 4 1/2", optimal back spacing would be 5".

    It looks like you are 1/2" short on back spacing front and rear at best. That might be OK on the front, but the rear may rub on the outside. 7mm is a bit more than 1/4", so if that 7mm is + offset, that would be 4 3/4" backspacing, which would be better. Can you fit them on the car to check?
     
    Last edited: Feb 2, 2016
  5. duke350

    duke350 Well-Known Member

    Test fit them and there was no issues. Mounted tires and installed them yesterday. Fit like a glove! Thanks guys. I would post a pic but for some reason I can't. Error message pops up every time.
     
  6. gstewart

    gstewart Well-Known Member

    With those 40 aspect ratio tires, I hope u have nice smooth roads to travel on. Where I live, with oure "smooth" (not so) roads, aspect 60 is about it.
     

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