The rear suspension that could have been

[jes_csx]

Again, look at this shot the OP previously posted (we need more!)

Now look closely at the following Explorer IRS chunks, studying the ribbing very carefully...

Until we see more images that point to the contrary, that differential chunk is looking very much like that of the Explorer/Mountaineer.

Some interesting reading on the 'to be' S197 IRS...
DrivingEnthusiast | Ford Mustang – IRS

Tob

It is definitely the same carrier. Like I said earlier, its no surprise they would use an off the shelf part if suited the application. According to my "source", wheel hop was absolutely not an issue. He kept stressing it was 1. cost, 2. cost and 3. cost.
More pics on the way.

 

[jes_csx]

OK, here is a link to a quick gallery I just put up. These are the only pictures I have right now.
irs gallery

 

[mblgjr]

Very cool all around to see.

So what's the plans for this unit? Install? Sell for copious sums of cash? Make replicas? How about some back to back track testing between stick vs. IRS in an otherwise stock car?

 

[mullens]

Ok, so it appears to be a prototype mule grade IRS assembly.

Looks heavy as stink.

I think I speak for most everyone here (esp. those of us that own 03/4 IRS cars)...I'm soooo glad they went with a stick axle and not an adapted IRS. Other than some very random potholes, I have no complaints with the stick axle in the new body.

+1. For high HP beasts like ours, give me a live axle any day. Half shafts tend to break with 600 ft lbs of tq and the benefits don't outweigh the cost. Show me one rail with IRS....

 

[ac427cobra]

Show me one rail with IRS....

A rail has one purpose. It doesn't have to ride particularly well, it doesn't have to go around corners and it never goes out to the store or on pleasure cruises! :idea:

But having said that, I'm pretty sure most people around here know how big of an IRS proponent I am. And I love my Shelby on the race track. (not the 1,320') But it's like wrestling a hippopotamus on the track. This car cannot stand ANY additional weight and that IRS assembly looks heavy! I'll give up a little in the handling department to save a little in the weight department.

FWIW

:thumbsup::coolman::beer:

 

[mblgjr]

I'm about to thread hijack...(sorry).

But if this would have been beneficial on the track, why didn't Multimatic/FR500C program use them or try 'em at some point?

I think a proper IRS can be a great thing; but mostly this parts find has historical significance and is rare; which is the whole point of this thread.

/end hijack.

 

[mullens]

A rail has one purpose. It doesn't have to ride particularly well, it doesn't have to go around corners and it never goes out to the store or on pleasure cruises! :idea:

But having said that, I'm pretty sure most people around here know how big of an IRS proponent I am. And I love my Shelby on the race track. (not the 1,320') But it's like wrestling a hippopotamus on the track. This car cannot stand ANY additional weight and that IRS assembly looks heavy! I'll give up a little in the handling department to save a little in the weight department.

FWIW

:thumbsup::coolman::beer:

Just being a little facitious....
I've had IRS on my 03 Term and SRT8, and I really don't see what all the fuss is about. But then, I don't oval track the car. My 3.55 pumpkin is good enough for what I use it for.

 

[me32]

note that he says "my well-placed sources". yea, look how right on his "well-placed sources" have been in the past, with that 2008 boss mustang powered by a 5.0l, the ecoboost 3.5l showing up in the 2011 mustang, the twin turbo 5.0l showing up in the GT500, etc.
i think i'll believe that ford 'lied' when i hear it from someone more reliable than the joke that is motortrend. i'll believe a random 1 post internet yahoo before i'll believe them.

im gonna agree motortrend can never get anything right about fords. in fact they dont even like fords. there chevy guys

 

[Dave07997S]

A rail has one purpose. It doesn't have to ride particularly well, it doesn't have to go around corners and it never goes out to the store or on pleasure cruises! :idea:

But having said that, I'm pretty sure most people around here know how big of an IRS proponent I am. And I love my Shelby on the race track. (not the 1,320') But it's like wrestling a hippopotamus on the track. This car cannot stand ANY additional weight and that IRS assembly looks heavy! I'll give up a little in the handling department to save a little in the weight department.

FWIW

:thumbsup::coolman::beer:

On a normally aspirated car in the 3650 range though with 412hp ala GT would be a nice setup. Lighter wheels, seats and such to get that car in the 3500lb range and it would be so fun at the track.

With the rumored Al. block in the GT500 I would gladly give the 80+lbs back to the rear of the car in unsprung weight and not to mention the better weight distribution.

The GT500 is amazing for what it does and I do understand that weight is the true enemy of these cars.

Dave

 

[Ry_Trapp0]

I'm about to thread hijack...(sorry).

But if this would have been beneficial on the track, why didn't Multimatic/FR500C program use them or try 'em at some point?

I think a proper IRS can be a great thing; but mostly this parts find has historical significance and is rare; which is the whole point of this thread.

/end hijack.

grand-am rules require factory style suspension using factory pickup points. in fact, the control arms are the GT500 stamped steel pieces with stiffer bushings(and an absurd price tag in the FRPP catalog).

on a side note, just consider that for a second. the mustang is using, basically, a factory suspension with stiffer springs and struts, as are its competitors the M3, 911, etc. now, i'll be the first to admit that the FR500C loses a little in the corners and gains it back on the straights vs those cars, but it certainly doesn't lose much in the corners at all. props to ford, impressive work with the S197!

 

[ac427cobra]

Just being a little facitious....
I've had IRS on my 03 Term and SRT8, and I really don't see what all the fuss is about. But then, I don't oval track the car. My 3.55 pumpkin is good enough for what I use it for.

No problem. ;-) But until you drive a Mustang hard enough to pass a Z06 on a racetrack, you won't be able to fully appreciate all of the benefits of an IRS. :-D

 

[chuckstang]

After driving my GT500 with a Watts link rear end vs standard rear, I can def say an IRS would make it handle much better

 

[jes_csx]

Being the OP and specifically NOT wanting this to turn into another SRA vs IRS debate has made me bite my tongue several times when reading some of these responses. I think some people are missing the big picture. I have nothing against the SRA in the Mustang and Ford obviously did a great job making "old" tech function very well (much like GM and the pushrod LS). The Mustang is a "bang for the buck" application, and in that context the SRA makes sense. The GT500 is in another category and considering its weight and use of supercharging I think its pretty obvious 9 out of every 10 people who would want to seriously mod one would be looking for more straight line acceleration, not roadracing prowess.
However, this notion that somehow an IRS or more specifically a S197 IRS (in a platform designed to go either direction from the start) is somehow inferior to an SRA in anything other then cost to performance does not hold water. Citing the "adapted" S95 IRS as a reference is anecdotal evidence at best... but citing a dedicated drag car? Really? Also, I do not understand the notion that a high-torque capacity IRS would somehow be a nearly impossible engineering feat exclusive to the GT500 in the automotive world. Does anyone thinking that a project such as this farmed out to Roush would produce underperforming components? Do you think Roush engineers would assume All GT500 owners are going to leave their cars bone stock, especially after following up the Ford GT program?
Production cars are built based on compromises between the engineers, the bean counters and those analyzing the target demographic. In this case , very understandable, the SRA won. Does this mean an IRS would be flawed or underperform, or that the SRA is superior? Absolutely not.
Back to the real topic here.... this is a very interesting piece of Ford performance history. It is an exciting topic for me and I'm a bit shocked that I even have the opportunity to share it. I am an uber-lurker on many forums and figured this would be the best place to start talking about this thing.
I am lucky enough to work for a guy that has been restoring Shelby Mustangs, Boss's and Cobras for over 30 years. He is also one of the founders of the Shelby American Collection in Boulder, CO Shelby American Museum and I have the privilege of being the Museums webmaster and and having the museums digital archives. My present day Ford "insider knowledge" is practically nonexistent (my college roommates dad was an advanced powertrain engineer in 94 and had a 93 lx notch running a DOHC 4.6 and I had a good friend who did some work on the marauder intake through Roush thats about as close as it gets)... but I do know a few things when looking back. This piece definitely fits in the "very cool" category. At this point I have no idea what will happen with it. I'm still waiting for it to get shipped here so I can study the crap out of it!

 

[mblgjr]

Ah C'mon; you knew it would derail into an IRS/SRA a little bit.

It's not that it would be some engineering miracle that the IRS could be completely functional and better all around...FACT...it could be.

BUT...when you put bean counters in the picture the whole thing falls apart because they make sure the product is "just enough" to get the job done and no more.

And you know the GM LS series was touched by God, so you can't compare it :lol:

A+ for coolest parts find
A+ for rarity
F- if you don't install it and try it out.

 

[jes_csx]

Ah C'mon; you knew it would derail into an IRS/SRA a little bit.

It's not that it would be some engineering miracle that the IRS could be completely functional and better all around...FACT...it could be.

BUT...when you put bean counters in the picture the whole thing falls apart because they make sure the product is "just enough" to get the job done and no more.

And you know the GM LS series was touched by God, so you can't compare it :lol:

A+ for coolest parts find
A+ for rarity
F- if you don't install it and try it out.

Trust me, If I had a S197, I'd be all over it! But sadly I dont right now and the one friend I know who would have been great to work with on this (an aerospace engineer) sold his car for a new SHO because he just got married and has a baby on the way. I guess he figured his 69 mach with a 650+hp FE stroker and Full TCP suspension etc was enough 'stang for right now :rockon:
I'm knee deep in the old cars, not so much with the new... but I'm working on it! I'm a Shelby dealer with a direct line to the top, but traditionally thats not where our business is... we got into it mainly to do aluminum FIA Cobras.

 

[Tob]

grand-am rules require factory style suspension using factory pickup points. in fact, the control arms are the GT500 stamped steel pieces with stiffer bushings(and an absurd price tag in the FRPP catalog).

I assume you are referring to the front control arms, as the FR500C uses a tubular rear LCA.

From here. The arms are no longer available.


And while the front LCA is indeed a stock stamping, the ancillary pieces are all aftermarket...
- longer ball joints
- higher durometer bushings
- unique caster adjustment bushings and hardware

The stamping itself is an award winning piece developed and manufactured by Multimatic, which coincidentally was responsible for the on-track devlopment of the FR500C along with final assembly. In other words, the arm really is a bit more than a stock piece with stiffer bushings. That is all.;-)

On edit (continued hijack)...Multimatic also did the Mustang rear lower and upper control arms, in addition to the front control arms (pg 5 of the linked pdf).

 

[jes_csx]

Hijacks containing relevant information and clarifications are cool :thumbsup:

 

[Ry_Trapp0]

I assume you are referring to the front control arms, as the FR500C uses a tubular LCA.

From here. The arms are no longer available.


And while the front LCA is indeed a stock stamping, the ancillary pieces are all aftermarket...
- longer ball joints
- higher durometer bushings
- unique caster adjustment bushings and hardware

The stamping itself is an award winning piece developed and manufactured by Multimatic, which coincidentally was responsible for the on-track devlopment of the FR500C along with final assembly. In other words, the arm really is a bit more than a stock piece with stiffer bushings. That is all.;-)

On edit (continued hijack)...Multimatic also did the Mustang rear lower and upper control arms, in addition to the front control arms (pg 5 of the linked pdf).

oh, i know where i messed up. the FRPP GT 'upgrade' control arms are the GT500 units. thanks for the correctoin! i believe i was correct about stock pickup points though, right?

 

[Tob]

I believe so, Ry.

Tob

 

[ac427cobra]

Hijacks containing relevant information and clarifications are cool :thumbsup:

Hijacks are a part of internet message board life. ;-)

Be glad you're not in the Cobra R Forum! :-D