IRS to SRA....the whole shabang

ous2418

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Neither a GT nor a GT500 is a "Sports Car". :read::idea:

correct yea i thought about that after the post. but honestly ive had both sra and irs in these cars. as far as handling their was a difference but once setup right minimal at most.
 

Black Sex

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When I did my SRA it cost me about 2200, for every thing brand new. Its all 31 spline FMS. Steeda rear suspension parts. After I had everything done I parted out my (broke) IRS for $1000. So I have about 1200 into the swap. It wouldve been close to that much to fix the IRS. So thats my reasoning. The ride quality Isnt all that much different. Yes it doesnt handle as good but I just got the stuff to get it driving again. I might build up the SRA to make it hadle alittle better or I might trade it for a built IRS some day (any takers). Am I unhappy with the my decision or the way the car rides and handles...NO. All I know now it I can drop the clutch at 5-6Krpm at the track and not worry about it.
 

unit213

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Don't put a stick axle in a Cobra! :nonono: Unless you're going to trailer the car to the drag strip and never drive it on the street. :-D

It's just a Mustang. It's not like it's a Ferrari.

My advice would be to not spend a single penny on anything related to the
IRS, unless it's money spent to remove it.
 

ac427cobra

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It's just a Mustang. It's not like it's a Ferrari.

My advice would be to not spend a single penny on anything related to the
IRS, unless it's money spent to remove it.

I am merely trying to educate the uninformed. :read:

Writing you off as a lost cause. ;-)
 

unit213

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I am merely trying to educate the uninformed. :read:

Writing you off as a lost cause. ;-)

Mutually agreed since you are sitting on the opposite end of the lost cause boat. ;-)

OP - very sorry to see the carnage. Best of luck to you sir! Get that SRA
and never look back! :beer:
 

rotor_powerd

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Did it ever occur to you that NO* modern sports car comes from the factory with an SRA?!?! :read::idea:


* zero, zilch, zip, nada


Well, since a Mustang isn't a sports car, then why would you want a heavily compromised IRS under the rear when a properly setup SRA will do the job just as well with a lot less weight.
 

ac427cobra

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Mutually agreed since you are sitting on the opposite end of the lost cause boat. ;-)

Here are the some of the problems Cobra owners face. Their car was designed to handle about 390 RWHP when it was NEW. Specifically the IRS. I'll bet less than 5% of Cobra owners reading this have less than 400 RWHP. Unfortunately for many Cobra owners, they are unaware how compromised the IRS was delivered from the factory. But their first mod is always a pulley, CAI and a tune or even better, a KB or Whipple. The first mod is NEVER beefing up the IRS. Hence all of the IRS problems we see on a continual, never ending basis. :( As the rubber in the IRS ages and wears, EVERY single Cobra owner will experience what the OP has experienced unless they address this issue.

It was obvious to some, that Mach 1's and GT's have much fewer rear end problems than Cobras. So a few people started doing SRA conversions and now it seems to be a trend. I like the fact that most of the people that do these SRA conversions will admit their car doesn't ride or handle as well as it did with the IRS. But some are stubborn about that and won't admit to it. :poke:

I hated the compromised IRS Ford gave me but it was for different reasons than most people here care about. It was downright frustrating for me getting passed by Z06's on track. Until I removed all of the rubber in my IRS it was too sloppy to enable me to corner fast at the track. After eradicating all of the rubber in the IRS, it was me spanking the Z06's like redheaded stepchildren. :-D

Drag racers and performance minded street drivers are faced with the same problem. You can't expect an IRS to stay together, be reliable and not break when all of the rear suspension components are mounted in silly putty.

OP - very sorry to see the carnage. Best of luck to you sir! Get that SRA
and never look back! :beer:

The good news is with an SRA, you can add a torque arm and a Watts link and it will handle ALMOST as good as an IRS, but it will NEVER ride as good. ;-)


Well, since a Mustang isn't a sports car, then why would you want a heavily compromised IRS under the rear when a properly setup SRA will do the job just as well with a lot less weight.

The IRS was only compromised as it came from the factory. It can be fixed. :idea:

No, the SRA will NOT do the job just as well. Far from it!! It doesn't handle or ride as well. The Mustang is already front end heavy and rear end light. You are going to throw that balance off even more and at the same time you're also going to be ADDING a crapload of rear unsprung weight.

For drag racers, an SRA is certainly a viable option. That I will fully admit. But for the VAST majority of Cobra owners that use their cars as daily drivers, they will be MUCH happier investing in their IRS and not bastardizing their cars.

:thumbsup::coolman::beer:
 

rotor_powerd

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The IRS is compromised, bushing upgrade or not. If the chassis was designed for a true IRS setup, keep it all way. For the IRS-in-a-box that was stuffed under these cars as an afterthought..... it's a waste. After working with both/riding in both setups daily/driving both setups aggressively, you'll never convince me that a properly setup solid is not the way to go with these cars. Aside from the exhaust cosmetics, I don't miss my IRS one bit.

Just my opinion from experience, I just can't say I would ever recommend anyone keep their IRS that's debating the switch.
 

mu22stang

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The IRS is compromised, bushing upgrade or not. If the chassis was designed for a true IRS setup, keep it all way. For the IRS-in-a-box that was stuffed under these cars as an afterthought..... it's a waste. After working with both/riding in both setups daily/driving both setups aggressively, you'll never convince me that a properly setup solid is not the way to go with these cars. Aside from the exhaust cosmetics, I don't miss my IRS one bit.

Just my opinion from experience, I just can't say I would ever recommend anyone keep their IRS that's debating the switch.

Please list the compromises of the Cobra's IRS. At least justify the propaganda filled statement highlighted in red. This "IRS-in-a-box" wasn't just "stuffed" in to sell cars and read good on paper. It was a fully engineered piece, castrated only by bushings.
 
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unit213

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The good news is with an SRA, you can add a torque arm and a Watts link and it will handle ALMOST as good as an IRS, but it will NEVER ride as good. ;-)

Again, it's a Mustang. If you want ride quality, buy a BMW. I'll buy a Z06 if I want to carve corners. My solid axle does just fine on the street in corners and it's far superior at the track. The rear end isn't a limiting factor in turning. The 335 Hoosier drag radials are...which is perfectly fine by me.

My IRS is right where it should be...sitting on a storage shelf. It's almost comical that there are Cobra "purists" out there. It's a low dollar Mustang on an archaic platform. It's not
like we own some exotic car that should never be touched.
 
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rotor_powerd

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Please list the compromises of the Cobra's IRS. At least justify the propaganda filled statement highlighted in red. This "IRS-in-a-box" wasn't just "stuffed" in to sell cars and read good on paper. It was a fully engineered piece, castrated only by bushings.

A "fully engineered" IRS isn't mounted inside a subframe. The rear in these cars is an afterthought, at best. Props to those who try to make it work, and have some success, but it will never work as well as an IRS in a chassis that was designed around it. You can't just take a chassis with a solid rear, and make an IRS fit and expect anything out of it, especially when you constrain yourself to using the same pickups on the frame and everything..... it's a cheesy setup is all it is.
 
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ac427cobra

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Again, it's a Mustang. If you want ride quality, buy a BMW.

Although BMW builds a very nice car, you will never see me in one.

I'll buy a Z06 if I want to carve corners.

There are VERY few things I find more entertaining than passing Z06's with a Mustang on the race track! It REALLY burns their ass!! :dancenana:

My IRS is right where it should be...sitting on a storage shelf. It's almost comical that there are Cobra "purists" out there. It's a low dollar Mustang on an archaic platform. It's not
like we own some exotic car that should never be touched.

Everybody has a favorite car. My favorite cars are ALL Mustangs. (ok, I also have an '89 SHO as well) I like Mustangs so much I have four of them. I also like to mod them so they can do things that Mustangs don't normally do. Things like going fast, handling well and stopping.

Some people think a stock Mustang handles pretty well put it's a pathetic sight driving one at it's cornering limit.

To each his own.

:thumbsup::coolman::beer:
 

Smacked_in_ATL

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Reading comments in here by SlowSVT and Bruce make me not want to even post. Good luck OP, hope you figure it out. SlowSVT, you are COMICAL AT BEST.
 

SlowSVT

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A "fully engineered" IRS isn't mounted inside a subframe. The rear in these cars is an afterthought, at best. Props to those who try to make it work, and have some success, but it will never work as well as an IRS in a chassis that was designed around it. You can't just take a chassis with a solid rear, and make an IRS fit and expect anything out of it, especially when you constrain yourself to using the same pickups on the frame and everything..... it's a cheesy setup is all it is.

This is a rather vague statement and I was wondering if you could elaborate on exactly how the chassis engineers at Ford botched the IRS installation in the Mustang? Sounds like you have some insights on this topic some of us are unaware of.
 

SlowSVT

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Reading comments in here by SlowSVT and Bruce make me not want to even post. Good luck OP, hope you figure it out. SlowSVT, you are COMICAL AT BEST.

You didn't want to post here yet you overcame your inhibition and managed to respond anyhow. That’s pretty impressive. I am happy that somehow I was able to amuse you. Perhaps you could return the favor and explain what I said that brightened your day so?


:pop:
 

2001SVTsnake

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you will always find the IRS nutswinggers who think its the greatest thing to hit the planet. i will admit it does drive nice but i could careless on handling only going fast in a straight line



i swapped to a SRA...my car is a straight line car only, i dont go taking corners at 50+mph its not my thing. IRS was just to damn expensive to beef up compared to the price of a SRA. also the SRA is alot lighter and less moving parts..
 
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Posi

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I've got every mod but the kitchen sink on my car and it still hops. Now granted I haven't gone out and done the "correct" alignment of driving it and shimming it but quite honestly I don't have the time to do it. It's wheel hopped since day one and I'm done with it.

I'm a Redneck and like to lay marks some times. It's either 1. Make sure it hooks or 2. Make sure I blow the tires off. Anything else and it'll hop. Period. My car seems to do it worse than about any other so I'm throwing in the towel. Plus it's more for drag racing.

SRA here I come.:banana:
 

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