Spring isolator to lower rear?
#1
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Guys that have swapped out to a 9" rear in particular (not sure if the 12 bolt and S60 are the same) have to deal with a higher spring perch with raises the rear end up. Having already lowered my car before the 9" the rear now sits 1.25" higher than the front, which looks terrible.
Are there any isolators that fit which give a lower stance, at least 1/2" or so? Or has anyone cut down the stock isolators? I'm not a fan of the heater hose mod, seen too many stories of the spring rubbing right through the hose.
Are there any isolators that fit which give a lower stance, at least 1/2" or so? Or has anyone cut down the stock isolators? I'm not a fan of the heater hose mod, seen too many stories of the spring rubbing right through the hose.
#6
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Found some that may work, just not sure on the drop. Off a 99-04 cobra, from what I read both cars use a 5.5" spring diameter. For the price I may try it, they appear to go deep to shallow like our OEM isolators.
They are on amazon, search "cobra irs spring isolator."
They are on amazon, search "cobra irs spring isolator."
Last edited by BrntWS6; 03-25-2017 at 03:33 PM.
#7
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Would something like these work ?
https://www.summitracing.com/parts/mrg-1285/overview/
https://www.summitracing.com/parts/mrg-1287/overview/
https://www.summitracing.com/parts/mrg-1285/overview/
https://www.summitracing.com/parts/mrg-1287/overview/
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#8
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Maybe, not sure how well it would hold being split. They have the one I was looking at as well, just not sure how much height is going to be affected.
https://www.summitracing.com/parts/ptp-6-1709/overview/
another, they are not good giving measurements on a lot of these.
https://www.summitracing.com/parts/m...0047/overview/
https://www.summitracing.com/parts/ptp-6-1709/overview/
another, they are not good giving measurements on a lot of these.
https://www.summitracing.com/parts/m...0047/overview/
Last edited by BrntWS6; 03-26-2017 at 02:39 PM.
#10
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3rd and 4th gen isolators are the same. There would be no gain from swapping to them. Removing the isolator and doing the heater hose mod usually gets you about 1/2-3/4" of drop in the back. Not much. If you are looking for a 1-1.25" drop, we have rear springs that will work for you to level the car out
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#12
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check out https://www.mcmaster.com/#raw-materials/=16xrqbc
under rubber - neoprene sheets and bars,
you can sort on size and durometer,
guessing something around 50A hardness.
under rubber - neoprene sheets and bars,
you can sort on size and durometer,
guessing something around 50A hardness.
#13
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3rd and 4th gen isolators are the same. There would be no gain from swapping to them. Removing the isolator and doing the heater hose mod usually gets you about 1/2-3/4" of drop in the back. Not much. If you are looking for a 1-1.25" drop, we have rear springs that will work for you to level the car out
https://ls1tech.com/forums/suspensio...inch-drop.html
#14
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So I got around to testing out a set of rear spring isolators for a 99-04 Cobra, they fit very well and dropped the car 1/2". I know the heater hose was way cheaper and probably would have been okay but I wanted to do it this way. Here is what I used...
![Name: 20170402_152305_zpsdhnqocym.jpg
Views: 3023
Size: 106.1 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587167d1501215222-spring-isolator-lower-rear-20170402_152305_zpsdhnqocym.jpg)
They are ramped like the OEM isolators.
![Name: 20170402_152254_zpsvktbi0vx.jpg
Views: 3516
Size: 108.6 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587168d1501215222-spring-isolator-lower-rear-20170402_152254_zpsvktbi0vx.jpg)
Stock Isolator
![Name: 20170402_151945_zps6ll3m4im.jpg
Views: 2904
Size: 90.2 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587169d1501215222-spring-isolator-lower-rear-20170402_151945_zps6ll3m4im.jpg)
vs Prothane isolator
![Name: 20170402_152017_zpsnz1o0qvv.jpg
Views: 2909
Size: 88.5 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587170d1501215222-spring-isolator-lower-rear-20170402_152017_zpsnz1o0qvv.jpg)
Starting measurement was 3.25" from the fender, I used the upper line on my tire.
![Name: 20170402_130604_zpswpai6epg.jpg
Views: 2922
Size: 87.4 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587171d1501215222-spring-isolator-lower-rear-20170402_130604_zpswpai6epg.jpg)
After the swap was 2.75"
![Name: 20170402_162521_zpsh54dcv16.jpg
Views: 3037
Size: 101.9 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587172d1501215222-spring-isolator-lower-rear-20170402_162521_zpsh54dcv16.jpg)
Closed the front to rear gap a bit from going to a 9" which was my goal. Cost was $30.
![Name: 20170402_152305_zpsdhnqocym.jpg
Views: 3023
Size: 106.1 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587167d1501215222-spring-isolator-lower-rear-20170402_152305_zpsdhnqocym.jpg)
They are ramped like the OEM isolators.
![Name: 20170402_152254_zpsvktbi0vx.jpg
Views: 3516
Size: 108.6 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587168d1501215222-spring-isolator-lower-rear-20170402_152254_zpsvktbi0vx.jpg)
Stock Isolator
![Name: 20170402_151945_zps6ll3m4im.jpg
Views: 2904
Size: 90.2 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587169d1501215222-spring-isolator-lower-rear-20170402_151945_zps6ll3m4im.jpg)
vs Prothane isolator
![Name: 20170402_152017_zpsnz1o0qvv.jpg
Views: 2909
Size: 88.5 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587170d1501215222-spring-isolator-lower-rear-20170402_152017_zpsnz1o0qvv.jpg)
Starting measurement was 3.25" from the fender, I used the upper line on my tire.
![Name: 20170402_130604_zpswpai6epg.jpg
Views: 2922
Size: 87.4 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587171d1501215222-spring-isolator-lower-rear-20170402_130604_zpswpai6epg.jpg)
After the swap was 2.75"
![Name: 20170402_162521_zpsh54dcv16.jpg
Views: 3037
Size: 101.9 KB](https://ls1tech.com/forums/attachments/suspension-brakes/587172d1501215222-spring-isolator-lower-rear-20170402_162521_zpsh54dcv16.jpg)
Closed the front to rear gap a bit from going to a 9" which was my goal. Cost was $30.
#15
12 Second Club
iTrader: (48)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
So I got around to testing out a set of rear spring isolators for a 99-04 Cobra, they fit very well and dropped the car 1/2". I know the heater hose was way cheaper and probably would have been okay but I wanted to do it this way. Here is what I used...
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_152305_zpsdhnqocym.jpg)
They are ramped like the OEM isolators.
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_152254_zpsvktbi0vx.jpg)
Stock Isolator
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_151945_zps6ll3m4im.jpg)
vs Prothane isolator
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_152017_zpsnz1o0qvv.jpg)
Starting measurement was 3.25" from the fender, I used the upper line on my tire.
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_130604_zpswpai6epg.jpg)
After the swap was 2.75"
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_162521_zpsh54dcv16.jpg)
Closed the front to rear gap a bit from going to a 9" which was my goal. Cost was $30.
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_152305_zpsdhnqocym.jpg)
They are ramped like the OEM isolators.
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_152254_zpsvktbi0vx.jpg)
Stock Isolator
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_151945_zps6ll3m4im.jpg)
vs Prothane isolator
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_152017_zpsnz1o0qvv.jpg)
Starting measurement was 3.25" from the fender, I used the upper line on my tire.
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_130604_zpswpai6epg.jpg)
After the swap was 2.75"
![](http://i134.photobucket.com/albums/q97/BrntWS6/20170402_162521_zpsh54dcv16.jpg)
Closed the front to rear gap a bit from going to a 9" which was my goal. Cost was $30.
#17
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Thanks for the pics and info.
I'm sure you're happy with the results but is it lowered enough or you want it lower still?
What size tires do you have on the rear?
I have the same problem after swapping in my 12 bolt....I think I'll cut the rear springs for now and go the adjustable route in the future so I can better set the stance of the car.
I'm sure you're happy with the results but is it lowered enough or you want it lower still?
What size tires do you have on the rear?
I have the same problem after swapping in my 12 bolt....I think I'll cut the rear springs for now and go the adjustable route in the future so I can better set the stance of the car.
Last edited by WidowrRacing; 04-04-2017 at 03:40 PM.
#19
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Thanks for the pics and info.
I'm sure you're happy with the results but is it lowered enough or you want it lower still?
What size tires do you have on the rear?
I have the same problem after swapping in my 12 bolt....I think I'll cut the rear springs for now and go the adjustable route in the future so I can better set the stance of the car.
I'm sure you're happy with the results but is it lowered enough or you want it lower still?
What size tires do you have on the rear?
I have the same problem after swapping in my 12 bolt....I think I'll cut the rear springs for now and go the adjustable route in the future so I can better set the stance of the car.
No problem, I have 315's in the rear.
I actually have not uncovered the car and stood back to look at it yet. Hopefully warm months are not far away and I can pull it out of storage. I'm going to guess another 1/4" would have been ideal but anything is better than the 4x4 look I had.
#20
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It will def look better.
I have 315-35-17s on my 88 Mustang GT and at 25.6 they're a short tire but suit the car.
The 275-40-17 aren't much taller on the rear my 02 Z28...with the 12 bolt rear and size of
the rear quarters they look like a 215-60-15s.
I think these cars need a 26.5-27.5 tall tire to fill the rear wheel well properly.
I have 315-35-17s on my 88 Mustang GT and at 25.6 they're a short tire but suit the car.
The 275-40-17 aren't much taller on the rear my 02 Z28...with the 12 bolt rear and size of
the rear quarters they look like a 215-60-15s.
I think these cars need a 26.5-27.5 tall tire to fill the rear wheel well properly.