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Rearend fitment?

  • Thread starter Thread starter 66StangFastback
  • Start date Start date Sep 7, 2006
6

66StangFastback

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Jun 6, 2005
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norman, oklahoma
Sep 7, 2006
#1
  • Sep 7, 2006
  • #1
What's the narrowest rear that'll fit in a 66 fastback without any trouble?

I've found an 8.8 that's been narrowed to 55.25" from mounting surface to mounting surface, and was wondering if that would work for me, or if i would run in to trouble? Anyone know? I'd really like to jump on this deal if it'll work.
 
6

66StangFastback

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Jun 6, 2005
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norman, oklahoma
Sep 7, 2006
#2
  • Sep 7, 2006
  • #2
CMon guys, I KNOW someone around here would know.
 

68FBJJZ109

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Easton, PA
Sep 7, 2006
#3
  • Sep 7, 2006
  • #3
Well I would imagine that depends alot on what size tire and wheel your using. Also where the spring perches are. I am not sure how wide a stock 66 rear is but a friend of mine just got 59 9" which is 57.25 and that supposed to fit right in the 65-66's. You might run into trouble with the inner wheel wells. Though you might be able to compensate for that with backspacing.
 
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66StangFastback

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#4
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There aren't any spring eprches on it, I'd have them welded on to fit. Like you said, I'm wondering If I'd have trouble with the inner wheel wells, or if that could be compensated for with backspacing. I would think I'd have trouble with my stock wheels, and if that were the case I'd throw on some cheap wheels to be able to get by.

Thanks for the reply 68

Basically i want to know the limit of what can be run without cutting the inner wheel wells, and if any fitment problems could be compensated with different wheels.

Thanks guys.
 
C

chromedog

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worlds center for speed
Sep 7, 2006
#5
  • Sep 7, 2006
  • #5
the 57-59 9" is a direct bolt in... as long as you get the u bolt plates from the 9"car. the axle tubes are a larger diameter, but thats the only difference sizewise.
 
6

66Runt

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Jun 11, 2005
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Sep 7, 2006
#6
  • Sep 7, 2006
  • #6
Just run a wheel with less backspace

You're basically 1" shorter per side with the axle you want to buy than a stock rear end. As an example Instead of a 4.75" back space on a 17"x8" rim you could run a 3.75" backspace and have a nice deep looking rim. Reminiscent of the 5 spoke racing wheels on the original GT350. (IMO) this would look really sweet!

See if you can't photoshop some deep dish rims onto the back of your car to see what you think.

Good luck,

Scott
 
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66StangFastback

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Sep 7, 2006
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66Runt said:
You're basically 1" shorter per side with the axle you want to buy than a stock rear end. As an example Instead of a 4.75" back space on a 17"x8" rim you could run a 3.75" backspace and have a nice deep looking rim. Reminiscent of the 5 spoke racing wheels on the original GT350. (IMO) this would look really sweet!

See if you can't photoshop some deep dish rims onto the back of your car to see what you think.

Good luck,

Scott
Click to expand...


Thanks a lot man! That's exactly what I wante to hear! Glad to know it's do-able without wheels spacers or whatever.
 
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66StangFastback

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#8
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Also, what is the backspace on stock wheels like these?

* Not my car, found it on google images.
 

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mdjay

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Sep 7, 2006
#9
  • Sep 7, 2006
  • #9
The stock track width on a 65-66 rear end is 56" so you're only about 3/8" per side short. It can vary depending on axles, brakes and other issues so they go up to about 57"... I've seen the bare housings measure from just under 51 13/16" to about 52.25"
http://www.kevinstang.com/Ninecase.htm

Either way once mounted you will need to do some work fitting the wheels.
http://www.mustangdepot.com/OnLineCatalog/WheelParts/offsets.htm
 
6

66Runt

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Sep 7, 2006
#10
  • Sep 7, 2006
  • #10
Actually 56.25" when measured from the wheel mounting points

Which means I was incorrect. it's 1/2" per side.
Sorry about that. I'm still working on learning fractions

Thanks mdjay, I hate when I give out bogus info.

I do not know the back space for rally rims, or if there is a difference between the early rally rims or later model Rally rims.

Scott
 

LUCAFU1

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Tucson
Sep 8, 2006
#11
  • Sep 8, 2006
  • #11
the 65-66 rear housing is 52.25" long. add another 5' for axles it comes to 57.25". so basically that 8.8 is a inch shorter on each side. youll be okay.
 

Cannoball888

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Dec 25, 2005
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Gainesville, FL
Sep 8, 2006
#12
  • Sep 8, 2006
  • #12
66StangFastback said:
Also, what is the backspace on stock wheels like these?

* Not my car, found it on google images.
Click to expand...
4.25" if 7" wide.
 
6

66StangFastback

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Sep 8, 2006
#13
  • Sep 8, 2006
  • #13
Goddamnit, I just hate getting alll excited over something like this, only to later realize the part is only for local pick up. Alas, I live right smack dab in the middle of oklahoma and the damn part is in St. Louis.
 
6

66Runt

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Sep 9, 2006
#14
  • Sep 9, 2006
  • #14
What are your measuring points?

LUCAFU1 said:
the 65-66 rear housing is 52.25" long. add another 5' for axles it comes to 57.25". so basically that 8.8 is a inch shorter on each side. youll be okay.
Click to expand...

I've measured three rear ends all for the '65-'66 (8", 9" and 7.5"). All three were 56.25" from the wheel mounting flat of the drums. Not sure where your getting 57.25".
 

LUCAFU1

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Sep 10, 2006
#15
  • Sep 10, 2006
  • #15
i measured 2, my 66 *" and a 58/59 ford axle. I thne measure the axles so i could order some mosers and those were 30 3/8" and 26 1/8" which equals 56 1/2". then there is that gap inside the locker (axles dont touch), thats how i got 57 1/4" (estimate). but theres no way mine was less the 56 1/2". it sounds like maybe you took your measurements from the back of the axle flange? i would go and verify this tomarrow but ive seen then narrowed that rear 2" on each side.
 
6

66Runt

Member
Jun 11, 2005
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Sep 10, 2006
#16
  • Sep 10, 2006
  • #16
Nope

bolted the drums down and measured from the face of where the wheels mount.

******Edit*************

Well open mouth insert both feet. I just went back and checked my notes and, I'm a total moron. The measurements I got were 57.25". Sorry for any confusion this caused.

******End of edit********
 
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