Narrowing my 65 Mustang rear end

Discussion in 'Classic Mustang Specific Tech' started by htd34, Aug 2, 2011.

  1. I am in the process of ordering a 9" rear end from Quick Performance for my 65 Mustang Coupe which currently has the 8". I am wanting to narrow the rear end enough to where I can add backspacing to my rear wheels. I like the look of a "deep dish wheel" on the rear. Does anyone know how much I can narrow the rear end without making any changes to the wheel well area or interfering with the leaf springs? I am changing the leaf springs to the mideye 5 leaf to be able to lower the car 1" or so. I want to run 17x8 or 17x9 wheels with tire size big enough to look good but not rub. Does anyone know with this how much backspacing I would need? Just an FYI (if needed)...I am going to 4 wheel disk brake from Wilwood. Thanks for any help you can give.
  2. If you are not relocating your leaf springs inwards, then you do not need to narrow your rear end--everything can be done with backspacing.

    Find the Dodgestang wheel chart on the net as it gives actual examples of what wheels and BS work.
  3. Actually want he wants to do can't be done with just backspacing. He wants to put in an extra deep dish in the back.

    If you take 2 inches out of the rear (1 on each side), then you would want custom 17z8 with 3.75 backspacing. Sounds like a very expensive thing to do just for the 'look' of an extra deep dish and really wouldn't give you what I suspect you want which is the look you get of a car that is tubbed with a 4 link and has a 10 inch or larger rim with a 5-6 inch deep dish.
  4. Not really looking for that look. What I am wanting is to see a difference from the front wheels to the rear wheels. Doesn't need to be a lot just wanted it to be different. Probably going with a five spoke wheel of some kind. Thanks for all of the info!!!
  5. I just installed my narrowed 9" this week. I now fit 245/60/15's on 15x8 magnum 500's. Very tight fit though. It's a measure 20 times cut once situation. You wanna get it juuuuust right.

    For mine which was way over stock to begin with (so I had no choice but to shorten it) I took it a half inch short than stock on each side, which gives you and overall length of 56.25 inchs. I can't imagine going any shorter than that, I now have about .75" clearance from tire to leaf spring, and I may still need to roll the fender edge just a tad, but we'll find that out once I get her back on the road.

    The real issue with fitment comes from the front portion of the wheel well, it gets very narrow up there, and the inside body joint tends to flare out towards the tire a bit. But that can be persuaded with a hammer and a gentle touch to roll that in towards the center of the car.

    If you have any questions when you get to setting it up, feel free to give me a shout hdtony @

    By the way, I used strange engineering in Morton grove il to do the shortening on mine. Very nice work.
  6. Getting the measurements just right makes all the difference in the world. Finished it up today and snapped some pics

    Attached Files:

  7. Nice Tony. :nice: I Love Rangoon red and the Magnums too!

    Thought I'd show a similar pic of my car with 26x10's on 15"x 8" 4.5 bs wheels:


    The rear has been narrowed, the car was minitubbed, the leafs were moved in 3", and the frame/front of the outer wheel well was notched at the rear for future expansion--28 x10's on 10" wide Magnums with 5.5bs.

    Sneak peak of the 28's:


    Attached Files:

    Stan Hill likes this.
  8. Typically you want to buy your wheels/tires first, set them in place then measure for your rear end width.
  9. +1
  10. Local guy did this on his car, I think he took it too far IMO but Ill snap some pictures if he has it at the strip. I'm guessing its gotta be only 2.5-3" of BS on the wheels but its also a mini tub deal with relocated leafs with at least 10 or 12 wheels. Just kinda looks odd.
  11. Here are the pics.

  12. I can appreciate the work that went into that, but I really don't like the look. Especially with the flares
  13. How much is it narrowed and how much room did the mini tub kit give you?
  14. Mini tub with frame mod gave me nearly 3" on each side. IIRC, rear was narrowed 1 3/4" per side. I use a 5.5" BS 10" rim. Here is what it now looks like with the 28x10.5x15's: