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Got the posi rearend in, a few questions and some comments

  • Thread starter Thread starter SadbutTrue
  • Start date Start date Aug 2, 2004

SadbutTrue

Founding Member
May 1, 2002
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41
Granada Hills, California
Aug 2, 2004
#1
  • Aug 2, 2004
  • #1
I've been doing a posi 9 inch swap for a little while now, and.. well, its in... and it works. Doesn't sping the tires at 1/3rd throttle anymore, as a matter of fact even with the crappy 195s that are on there I have to actually want to burn out to do it, and when I do it leaves two fat strips of rubber... a welcome sight.

A few things I've noticed. The 3.25s do rev up faster than the old 2.8s did, but the car itself doesn't go a whole lot faster. I suppose this could be because my engine combo isn't aggressive enough to take advantage of the gears completely. Should I make any changes to my state of tune to take this into account, or is that just how it goes? Also, I can feel the 9inch in back, seems the extra weight makes the whole car feel more solid and larger.

Just for other's future reference, my driveshaft did need a new U-joint, but did not need to be shortened to mate up to the 9 inch. I'll try to get some pics up soon, thanks everyone for your help.
 

HistoricMustang

Active Member
Apr 11, 2003
2,359
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Confederate States of America
www.historicmustang.com
Aug 2, 2004
#2
  • Aug 2, 2004
  • #2
Welcome to the world of 9 inchers! I love both of mine.

Keep everyone posted.

HistoricMustang
www.historicmustang.com

 

mustang70

Founding Member
Nov 15, 2001
2,445
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48
48
San Diego
Aug 2, 2004
#3
  • Aug 2, 2004
  • #3
Maybe the extra weight of the 9 inch is overcoming the difference in gears.
 

zookeeper

Founding Member
Aug 25, 2001
3,415
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109
64
Rogue River, Oregon
Aug 2, 2004
#4
  • Aug 2, 2004
  • #4
If the extra 25lbs makes that big of a difference, he's got bigger problems than a simple tune up could cure
 

mustang70

Founding Member
Nov 15, 2001
2,445
2
48
48
San Diego
Aug 3, 2004
#5
  • Aug 3, 2004
  • #5
zookeeper said:
If the extra 25lbs makes that big of a difference, he's got bigger problems than a simple tune up could cure
Click to expand...


I dunno. I still have the 8" under my car.
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Aug 3, 2004
#6
  • Aug 3, 2004
  • #6
Changing to rear gear doesn't make it go faster,
justs gets it moving off the line quicker.
a good tune and test to get the best performance is what you should do next.

Wait till you hit that first wet spot on the road, Hang on.

PB
 
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