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66 mustang rearend

  • Thread starter Thread starter sangwitch
  • Start date Start date Apr 23, 2004
S

sangwitch

New Member
Apr 21, 2004
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Apr 23, 2004
#1
  • Apr 23, 2004
  • #1
OK guys i have another question. I am putting in a 302, 4spd in my 66 mustang. Should i use a 8 inch or 9 in rear end.
 

2bav8

Founding Member
Nov 30, 1998
2,511
1
47
Mesa, AZ
Apr 23, 2004
#2
  • Apr 23, 2004
  • #2
The 8" is a good rear end.
Unless you're going to be putting 350+ HP to the rear tires I'd keep the 8"
Its lighter and soakes up less HP than the 9" does.
 

NorCal66

New Member
Aug 12, 2003
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Virginia Tech, Blacksburg, VA HOME
Apr 23, 2004
#3
  • Apr 23, 2004
  • #3
Ditto, unless you have big power or slicks in your plans, the 8 inch will hold up fine.
 

RajunCajun

New Member
Nov 26, 2003
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Apr 23, 2004
#4
  • Apr 23, 2004
  • #4
so theoretically a well rebuilt 8" could handle a 393 stroker with aT3550 only on street tires?
 
R

Ronstang

New Member
Apr 4, 2004
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Houston Texas
Apr 23, 2004
#5
  • Apr 23, 2004
  • #5
RajunCajun said:
so theoretically a well rebuilt 8" could handle a 393 stroker with aT3550 only on street tires?
Click to expand...
That is questionalble. I wouldn't spend too much $$$ to build up the 8" since you will more than likely break it....I have broken an stock 9" carrier with a 351.
 

HistoricMustang

Active Member
Apr 11, 2003
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Confederate States of America
Apr 24, 2004
#6
  • Apr 24, 2004
  • #6
I use a 9", but we are beginning to see more and more 8" units that are road racing. It has to do with the less "rotating mass" of the 8" and therefore more rear wheel horsepower.

Currie builds a great rear end.

HistoricMustang
www.historicmustang.com
 
F

Ford4Fun

New Member
Mar 6, 2003
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Montana
Apr 24, 2004
#7
  • Apr 24, 2004
  • #7
Has anyone concidered the 8.8 irs out of the 80s and 90s t-birds?? It has its own subframe that would not be hard to mount in an early stang. I do not know the width but it would be close.
 
9

96 DOHC Cobra

Founding Member
Oct 14, 2001
542
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16
Cerritos, CA
Apr 24, 2004
#8
  • Apr 24, 2004
  • #8
Ford4Fun said:
Has anyone concidered the 8.8 irs out of the 80s and 90s t-birds?? It has its own subframe that would not be hard to mount in an early stang. I do not know the width but it would be close.
Click to expand...

I'm sure it's been considered. I think I've read somewhere that it's been done. Not a good option for an early Stang. Too wide. I think it's about six inches wider than a 65-66.
 

rbohm

Founding Member
Apr 12, 2002
6,698
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tucson,az
Apr 25, 2004
#9
  • Apr 25, 2004
  • #9
an 8" rear, properly prepped, will handle about 400hp, 350 with slicks at the dragstrip. another rear you might consider is the 8.8" out of an early 90's mustang gt. you would have to get rid of the stock suspension brackets, and weld on some leaf spring mounts, not hard to do, but you would have a rear that would handle about 95% of the hp that a 9" would, but it would be very close to the weight of the 8" rear, and you would have a large variety of components available for it. as to the Tbird IRS, i have considered it as a possibility, especially since i have seen it used under a 91 stang, but the subframe is large, heavy and bulky, and would require too much effort for the minimal, if any, gains you would get in ride or handling.
 

ratio411

Founding Member
Apr 21, 2002
3,870
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109
Pensacola FL
Apr 25, 2004
#10
  • Apr 25, 2004
  • #10
You can use either...
My vote is 9".
I have grenaded too many 8"s with just 302 power.
I suppose it would be more reliable with more money in parts and professional building, but there comes a point where a 9" can be had for less, due to it's popularity and wide range of aftermarket parts, and still be much stronger.
Good luck
Dave
 
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