1. Welcome to Jeeps.net!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Jeep discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other Jeep owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

79 CJ... What offset to prevent rubbing?

Discussion in 'Jeep CJ' started by ScottR, Mar 22, 2017.

  1. Mar 22, 2017 at 7:31 PM
    #1
    ScottR

    ScottR [OP] New Member

    Joined:
    Mar 22, 2017
    Member:
    #1196
    Messages:
    4
    Gender:
    Male
    Hello guys I'm a first time jeep owner and I need help. I recently came across a 1979 CJ5 jeep and I want to put some new rims and tires on it. It's got the original 7" rims and I want to put some offset rims with some 33" tires. My question is what offset do I need to keep tires from hitting frame when I turn? I was looking at some -13 offset rims. Is that enough or do I need more offset
     
  2. Mar 22, 2017 at 7:43 PM
    #2
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine Moderator

    Joined:
    Jul 19, 2016
    Member:
    #2
    Messages:
    4,042
    Gender:
    Male
    Welcome! I don't know much about that year, so hopefully someone can chime in with help.
     
  3. Mar 23, 2017 at 9:18 AM
    #3
    OFFGRID

    OFFGRID Well-Known Member

    Joined:
    Oct 3, 2016
    Member:
    #317
    Messages:
    2,018
    Gender:
    Male
    First Name:
    Peter
    Houston
    Vehicle:
    1979 Jeep CJ7, 258, TH350, NP208
    Howell fuel injection, header, HEI distributor, TH350, NP208, SOA lift with YJ springs in the front & GW springs in the Rear. AMC20 with G2 1 piece chromos trussed, Dana 30 with G2 chromos and 760x ujoints and MM Stainless Hubs, Geared 4.56. Tom Woods shafts, Metal cloaks, Caged, 37" Toyo MTs.
    Backspace is more important than offset. Offset changes based on the width of the wheel. -13 would probably be okay for an 8in wide wheel. Most common is 3.75in backspace. I would say keep it between 3.5 and 4 inches of back space. You will rub the leaf spring before you get into the frame. I run 37s on mine and I rub springs at full turn on the right side with 3.75 backspace. A little rub every now and then won't hurt you, and if you are really worried about it there are limiting screws or turn stop bolts on your steering knuckle that you can set to stop the wheel from turning any further. There is a very good write up on this subject in an earlier post.
     
  4. Mar 23, 2017 at 10:00 AM
    #4
    ScottR

    ScottR [OP] New Member

    Joined:
    Mar 22, 2017
    Member:
    #1196
    Messages:
    4
    Gender:
    Male
    So how I determine the backspace on the jeep. I'm sorry if I sound stupid but I've never dealt with this issue. I'm looking at putting 33X10.5X15 tires on 15X8 with the -13 offset so I should be good with that? I appreciate the help
     
  5. Mar 23, 2017 at 10:00 AM
    #5
    ScottR

    ScottR [OP] New Member

    Joined:
    Mar 22, 2017
    Member:
    #1196
    Messages:
    4
    Gender:
    Male
    Nice lookin jeep my the way.
     
  6. Mar 23, 2017 at 10:52 AM
    #6
    OFFGRID

    OFFGRID Well-Known Member

    Joined:
    Oct 3, 2016
    Member:
    #317
    Messages:
    2,018
    Gender:
    Male
    First Name:
    Peter
    Houston
    Vehicle:
    1979 Jeep CJ7, 258, TH350, NP208
    Howell fuel injection, header, HEI distributor, TH350, NP208, SOA lift with YJ springs in the front & GW springs in the Rear. AMC20 with G2 1 piece chromos trussed, Dana 30 with G2 chromos and 760x ujoints and MM Stainless Hubs, Geared 4.56. Tom Woods shafts, Metal cloaks, Caged, 37" Toyo MTs.
  7. Mar 23, 2017 at 11:22 AM
    #7
    ScottR

    ScottR [OP] New Member

    Joined:
    Mar 22, 2017
    Member:
    #1196
    Messages:
    4
    Gender:
    Male
    Thanks for the help. I found some info on offset and back spacing. I think I'm getting a handle on it now.
     
  8. Mar 23, 2017 at 11:45 AM
    #8
    OFFGRID

    OFFGRID Well-Known Member

    Joined:
    Oct 3, 2016
    Member:
    #317
    Messages:
    2,018
    Gender:
    Male
    First Name:
    Peter
    Houston
    Vehicle:
    1979 Jeep CJ7, 258, TH350, NP208
    Howell fuel injection, header, HEI distributor, TH350, NP208, SOA lift with YJ springs in the front & GW springs in the Rear. AMC20 with G2 1 piece chromos trussed, Dana 30 with G2 chromos and 760x ujoints and MM Stainless Hubs, Geared 4.56. Tom Woods shafts, Metal cloaks, Caged, 37" Toyo MTs.
    Backspace/offset chart for wheel width

    [​IMG]
     
  9. Mar 23, 2017 at 11:47 AM
    #9
    OFFGRID

    OFFGRID Well-Known Member

    Joined:
    Oct 3, 2016
    Member:
    #317
    Messages:
    2,018
    Gender:
    Male
    First Name:
    Peter
    Houston
    Vehicle:
    1979 Jeep CJ7, 258, TH350, NP208
    Howell fuel injection, header, HEI distributor, TH350, NP208, SOA lift with YJ springs in the front & GW springs in the Rear. AMC20 with G2 1 piece chromos trussed, Dana 30 with G2 chromos and 760x ujoints and MM Stainless Hubs, Geared 4.56. Tom Woods shafts, Metal cloaks, Caged, 37" Toyo MTs.

Products Discussed in

To Top