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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

1989 foxbody coupe irs swap needs

  • Thread starter Thread starter MFOXB89
  • Start date Start date Jul 4, 2018
M

MFOXB89

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Jul 4, 2018
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Jul 4, 2018
#1
  • Jul 4, 2018
  • #1
I recently got a hold of a shell, roller coupe. I’ve been buying parts for it to restore it. I want to work on the suspension & I know I want to do a irs swap, don’t know much about them I’ve read and done some research. “03-04” for good power & 3.55. The part on where I’m stuck is coilovers, brake upgrades. I’m going to do coilovers don’t know if I’m suppose to buy a rear cobra struds & also mines 4 lug, I know I have to upgrade on the brake lines, but changing to 5 lug what kind of brakes do I order fox brakes or cobra brakes? Any tips or help would be appreciated. Thank you for reading!
 

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eighty5fox

Mustang Master
Sep 29, 2016
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Jul 5, 2018
#2
  • Jul 5, 2018
  • #2
any 94-04 rear brakes will work you could either run gt or cobra
 
M

MFOXB89

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Jul 4, 2018
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Jul 5, 2018
#3
  • Jul 5, 2018
  • #3
eighty5fox said:
any 94-04 rear brakes will work you could either run gt or cobra
Click to expand...



Do I buy cobra brakes for the rear or regular brakes for a fox on the irs ?
 

eighty5fox

Mustang Master
Sep 29, 2016
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Jul 5, 2018
#4
  • Jul 5, 2018
  • #4
you could buy either set i belive the difference is the cobra brakes are a little bigger and use a different caliper bracket and rotor but the calipers are the same
 
M

MFOXB89

Member
Jul 4, 2018
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Jul 5, 2018
#5
  • Jul 5, 2018
  • #5
eighty5fox said:
you could buy either set i belive the difference is the cobra brakes are a little bigger and use a different caliper bracket and rotor but the calipers are the same
Click to expand...



What about coilovers?
 

eighty5fox

Mustang Master
Sep 29, 2016
286
303
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mass
Jul 5, 2018
#6
  • Jul 5, 2018
  • #6
pretty sure you need to run 99-04 cobra irs struts and coilovers. And i believe you can call maximum motorsports and they will help guide you in the right direction on spring rates and all of that fun stuff
 
M

MFOXB89

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Jul 4, 2018
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Jul 5, 2018
#7
  • Jul 5, 2018
  • #7
Okay thanks!
eighty5fox said:
pretty sure you need to run 99-04 cobra irs struts and coilovers. And i believe you can call maximum motorsports and they will help guide you in the right direction on spring rates and all of that fun stuff
Click to expand...
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
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Jul 5, 2018
#8
  • Jul 5, 2018
  • #8
You will need IRS specific coil overs. They come with a bracket that has to be welded into the rear shock tower. There used to be tubular lower irs control arms floating around....but i haven't seen them in a while.

You'll need 94- 95 front spindles and brake stuff. The 93 cobra brake booster and master cylinder are the best option for the brakes. You'll have to gut the factory proportion valve and use an adjustable one for best braking.

I use cobra front brakes on sn95 spindles with a cobra booster and a 98 v6 master cylinder and prop valve. My car stops well but I drove one with the 93 cobra master cylinder and adjustable prop valve.... that thing stopped on a dime and the pedal was a little tighter.

Mine stops on a nickle....it will lock the tires but its not as responsive.
 
M

MFOXB89

Member
Jul 4, 2018
10
1
13
San Antonio
Jul 5, 2018
#9
  • Jul 5, 2018
  • #9
90sickfox said:
You will need IRS specific coil overs. They come with a bracket that has to be welded into the rear shock tower. There used to be tubular lower irs control arms floating around....but i haven't seen them in a while.

You'll need 94- 95 front spindles and brake stuff. The 93 cobra brake booster and master cylinder are the best option for the brakes. You'll have to gut the factory proportion valve and use an adjustable one for best braking.

I use cobra front brakes on sn95 spindles with a cobra booster and a 98 v6 master cylinder and prop valve. My car stops well but I drove one with the 93 cobra master cylinder and adjustable prop valve.... that thing stopped on a dime and the pedal was a little tighter.

Mine stops on a nickle....it will lock the tires but its not as responsive.
Click to expand...


Good to know, thank you, I’m doing a coyote swap. Going with a 15-18 model engines.
 
Reactions: 90sickfox

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
6,945
5,816
213
Jul 5, 2018
#10
  • Jul 5, 2018
  • #10
Make sure you keep us posted on your build.

Coyote engines are still above my budget... but I've got IRS. Lol
 
M

MFOXB89

Member
Jul 4, 2018
10
1
13
San Antonio
Jul 5, 2018
#11
  • Jul 5, 2018
  • #11
90sickfox said:
Make sure you keep us posted on your build.

Coyote engines are still above my budget... but I've got IRS. Lol
Click to expand...


You’ll get there! & I will! I ordered back seat delete kit, engine bay to cover the holes. I still got lots to go but I’ll come as planned. It’s going to get painted next month.
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
6,945
5,816
213
Jul 5, 2018
#12
  • Jul 5, 2018
  • #12
Can you post pics ? We like pictures.
 
M

MFOXB89

Member
Jul 4, 2018
10
1
13
San Antonio
Jul 6, 2018
#13
  • Jul 6, 2018
  • #13
90sickfox said:
Can you post pics ? We like pictures.
Click to expand...




I’ll post when it starts getting painted and putting back together.
 

eighty5fox

Mustang Master
Sep 29, 2016
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Jul 6, 2018
#14
  • Jul 6, 2018
  • #14
yeah post some pics im currently doing a coyote swap also check out my build
 
M

MFOXB89

Member
Jul 4, 2018
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San Antonio
Jul 7, 2018
#15
  • Jul 7, 2018
  • #15
You can follow me on Instagram, @MFOXB89
 
M

MFOXB89

Member
Jul 4, 2018
10
1
13
San Antonio
Jul 7, 2018
#16
  • Jul 7, 2018
  • #16
eighty5fox said:
yeah post some pics im currently doing a coyote swap also check out my build
Click to expand...


You can follow me on Instagram, @MFOXB89 I’ll aprove it
 
G

Gfcobra04

Member
Sep 21, 2017
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1
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Texas
Jul 7, 2018
#17
  • Jul 7, 2018
  • #17
On rear brakes all mustangs 03/04 have same rear calipers. The difference is the cobra has vented rotors and all other mustangs have solid rotors. Therefore the cobra has thinner pads.
Gary
 
M

MFOXB89

Member
Jul 4, 2018
10
1
13
San Antonio
Jul 8, 2018
#18
  • Jul 8, 2018
  • #18
Gfcobra04 said:
On rear brakes all mustangs 03/04 have same rear calipers. The difference is the cobra has vented rotors and all other mustangs have solid rotors. Therefore the cobra has thinner pads.
Gary
Click to expand...



I’m going to go with willwood brakes. I want to upgrade.
 
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