No IRS for '07 Cobra
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From: SoCal
Originally posted by REDFIRESNAKE@November 8, 2004, 4:47 PM
If I lay down 40 large on a Cobra it better be keeping up with the new Corvette!
If I lay down 40 large on a Cobra it better be keeping up with the new Corvette!
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Hmmm.... $40k, beats a Vette, and still seats 4?
Sounds too good to be true. Especially since the Mustang is fighting size and weight. Add a lighter IRS (if its properly designed) and a heavier engine to get 400+ hp, and the nose-heavy balance is back with worse understeer. Which means a heavier sway and reduced rear suspension compliance.....
That being said, I have no doubt that it will be an incredible machine! And I would much rather have over the Vette, no matter who wins at the track! (it is a street car after all) The hp wars are sure heating up and it is great to see.
Now, if the friggin oil prices would stay low, we would have the best of both worlds. Why is it oil prices always seem to climb to stop hp wars? Government consipiracy, I tell you!
Sounds too good to be true. Especially since the Mustang is fighting size and weight. Add a lighter IRS (if its properly designed) and a heavier engine to get 400+ hp, and the nose-heavy balance is back with worse understeer. Which means a heavier sway and reduced rear suspension compliance.....
That being said, I have no doubt that it will be an incredible machine! And I would much rather have over the Vette, no matter who wins at the track! (it is a street car after all) The hp wars are sure heating up and it is great to see.
Now, if the friggin oil prices would stay low, we would have the best of both worlds. Why is it oil prices always seem to climb to stop hp wars? Government consipiracy, I tell you!
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I think it is unfair to call bs on CanadainStang. He works at AAI and would probably be privy to some kind of information along those lines. We'll see how things pan out.
Once again, the '05 Chassis is not a carbon copy of the DEW98 (X-type, LS, T-bird) chassis. It uses a few bits from that chassis. The rear underbody is different.
My opinion is that it is wrong to not put an IRS in a high-dollar SVT model, especially if all-around performance is desired. Drag racers will love a solid axle. It would be cool if they did offer both combinations, an IRS for the fans of the twisties and a "Drag Pack" option for the 1320 guys.
Once again, the '05 Chassis is not a carbon copy of the DEW98 (X-type, LS, T-bird) chassis. It uses a few bits from that chassis. The rear underbody is different.
My opinion is that it is wrong to not put an IRS in a high-dollar SVT model, especially if all-around performance is desired. Drag racers will love a solid axle. It would be cool if they did offer both combinations, an IRS for the fans of the twisties and a "Drag Pack" option for the 1320 guys.
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Originally posted by rhumb@November 8, 2004, 6:21 PM
I find this highly doubtful. To play in the league that the Cobra intends to, it will need to bring a good IRS. They certainly would NOT be trying to cram the existing Cobra's IRS, a rather stop-gap piece itself anyway, into the entirely different S197 frame.
The only way I think the Cobra could retain a live axle design and still retain any credibility as a high-end performance car would be to do something pretty high-tech and wild with the live axle in terms of materials and whatnot. The live axle's big achille's heel is its massive unsprung weight. Perhaps through liberal use of high strenth alloys, aluminum, magnesium, titanium and/or composites, they could drastically slash the unsprung weight. It would end up costing about as much or more than an IRS, but at least if they're having packaging issues, that would be a way to bypass that.
Can't understand why they would have so much trouble designing a new IRS for the S197 as there are plenty of 2+2 cars of similar size with fine IRS systems. But maybe they were just too shortsighted and penny pinching in the initial chassis design stages and didn't design it to accomodate an IRS later...?
As for the Vette, it does use a leaf spring at each end, as a spring, though any similarity to the old, steel multi-leaf springs found on so many cars of yore ends there. The Vette's is a composite construction, transversely arranged. Its advantages include very light weight, very low CG, takes up almost no room and also lasts much longer than a metal spring (coil or leaf), which tend to soften and sag with age. The only real downside I can think of is greater cost.
I find this highly doubtful. To play in the league that the Cobra intends to, it will need to bring a good IRS. They certainly would NOT be trying to cram the existing Cobra's IRS, a rather stop-gap piece itself anyway, into the entirely different S197 frame.
The only way I think the Cobra could retain a live axle design and still retain any credibility as a high-end performance car would be to do something pretty high-tech and wild with the live axle in terms of materials and whatnot. The live axle's big achille's heel is its massive unsprung weight. Perhaps through liberal use of high strenth alloys, aluminum, magnesium, titanium and/or composites, they could drastically slash the unsprung weight. It would end up costing about as much or more than an IRS, but at least if they're having packaging issues, that would be a way to bypass that.
Can't understand why they would have so much trouble designing a new IRS for the S197 as there are plenty of 2+2 cars of similar size with fine IRS systems. But maybe they were just too shortsighted and penny pinching in the initial chassis design stages and didn't design it to accomodate an IRS later...?
As for the Vette, it does use a leaf spring at each end, as a spring, though any similarity to the old, steel multi-leaf springs found on so many cars of yore ends there. The Vette's is a composite construction, transversely arranged. Its advantages include very light weight, very low CG, takes up almost no room and also lasts much longer than a metal spring (coil or leaf), which tend to soften and sag with age. The only real downside I can think of is greater cost.
We already know it handles better than the 04 Cobra's IRS and with 450-500hp, I'm sure there's probably launching problems vs. a live-axle setup.
The GT's suspension is beginning to prove itself as world class.....very impressive for an ox-cart rear end.
Motortrend said it had the quickest slalom time since the Cobra R.
As far as upsprung weight, I'm sure lighter rims may be in order, but how much of that will be offset by the larger rim/tire package.
I for one am very reassured at the capabilities of the live axle if this is true. Ford would not penny pinch on something this significant if it was a major issue.
As for straight line performance, I'm getting very excited at what kind of 0-60 and 1/4 mile times we may see with this setup and 450-500hp. We know it hooks up extremely well.
I know Canadian stang is definately in a position to give accurate info based on what i've seen in the past. The question is, is this a trial car (ie. they have IRS cars too) or is this the real deal?
Maybe if Amy gets that pic (one from the rear hopefully) we'll be able to tell.
The big question is, will the car community be able to embrace a top of the line mustang with a live axle. Even if it is capable, I think many will have a mindset that if it doesn't have IRS it won't perform.
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I seem to recall reading a comment from our chief engineer that they had already designed a lighter IRS for the 05 when feedback lead them to can it in favour of the solid. Thus leading to a "state-of-the art solid suspension". 
For what it's worth I have a 97 SVT without and it is waiting for a 99 up IRS. I have already put $ away for the next and I don't care as long as I can drive it like it out to be.
For what it's worth I have a 97 SVT without and it is waiting for a 99 up IRS. I have already put $ away for the next and I don't care as long as I can drive it like it out to be.
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Originally posted by REDFIRESNAKE@November 8, 2004, 5:47 PM
If I lay down 40 large on a Cobra it better be keeping up with the new Corvette!
If I lay down 40 large on a Cobra it better be keeping up with the new Corvette!
It just makes no sense to me that SVT would not even consider putting IRS on the new Cobra, especially since they're trying to give the Vette a run for its money. I know the current live-axle on the 05 GT is truely state-of-the-art and the it out performs the 03/04 Cobra's IRS setup, but still it, if the new Cobra is going to be on the same level as the new Zo6, it better dam well have a good IRS. I know that with 450-500+hp on tap, it's going to be difficult to have to put all that power onto the pavement, since past Cobra's that have IRS (99-01/03-04) are well known for axle-wind or "wheel-hop," I'm confident that with the new Cobra, SVT will have an amazing IRS setup that will be able to not only reduce that problem and be able to handle all that power, but will also allow for the car to out perform, or at least be on par with some of the better-handling IRS cars on the road.
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Originally posted by 03muzzy6+November 8, 2004, 11:02 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (03muzzy6 @ November 8, 2004, 11:02 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-REDFIRESNAKE@November 8, 2004, 5:47 PM
If I lay down 40 large on a Cobra it better be keeping up with the new Corvette!
If I lay down 40 large on a Cobra it better be keeping up with the new Corvette!
It just makes no sense to me that SVT would not even consider putting IRS on the new Cobra, especially since they're trying to give the Vette a run for its money. I know the current live-axle on the 05 GT is truely state-of-the-art and the it out performs the 03/04 Cobra's IRS setup, but still it, if the new Cobra is going to be on the same level as the new Zo6, it better dam well have a good IRS. I know that with 450-500+hp on tap, it's going to be difficult to have to put all that power onto the pavement, since past Cobra's that have IRS (99-01/03-04) are well known for axle-wind or "wheel-hop," I'm confident that with the new Cobra, SVT will have an amazing IRS setup that will be able to not only reduce that problem and be able to handle all that power, but will also allow for the car to out perform, or at least be on par with some of the better-handling IRS cars on the road. [/b][/quote]
That is definately where the concern comes in.
Its not that the Cobra can't be a world-class handling car with the live axle, but can it compete with the superior IRS setup on the Vette.
And as rhumb often points out, the live axle can come close to IRS level performance on a road course, but there is always a disadvantage (if only slight).......at least that is what my physics tell me.
Mind you, Hau is definately the one to ask about this one (chassis engineer).
This should be interesting.
Personally, the setup on the GT is the best compromise for me. I love the solid axle for its reliability and ability to put power to the pavement. I drive an IRS equiped car now so I know what its advantages are as well. The new setup lets me have my cake and eat it too.
However, if I was buying a Cobra, this would definately be a bigger issue.
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Originally posted by sharpie@November 8, 2004, 8:36 PM
ooopppss...but it is still fully independent, right??
ooopppss...but it is still fully independent, right??
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Look, there's a ton of tradeoffs in engineering. And I believe a good SRA can beat a mediocre IRS. But I think it is a little much to say it can do everything as good. If it could, no one (or few) would use IRS.
IRS has the potential to perform better and weigh less -- if it didn't, no one would use it. That doesn't mean it is always worth the costs. But physics says that one wheel being able to travel indepent of the other (with less mass) is going to have the potential to ride better and perform better than the alternative. That doesn't mean it will live up to that potential, or you can't get close. But the potential is there. (Just like AWD has the potential to out accelerate/out-perform FWD or RWD -- you may not be able to exploit that potential because of drive-train loss or added weight, but the physics or friction say it has the potential to be better).
IRS has the potential to perform better and weigh less -- if it didn't, no one would use it. That doesn't mean it is always worth the costs. But physics says that one wheel being able to travel indepent of the other (with less mass) is going to have the potential to ride better and perform better than the alternative. That doesn't mean it will live up to that potential, or you can't get close. But the potential is there. (Just like AWD has the potential to out accelerate/out-perform FWD or RWD -- you may not be able to exploit that potential because of drive-train loss or added weight, but the physics or friction say it has the potential to be better).
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To me, what is interesting about this is more what might be possible explainations for a live axle car running around with an upgraded motor.
That's how these rumours start -- someone sees a mule or stumbles on plans and figures they've seen the next Cobra. Maybe they've seen something real, but drawn the wrong conclusions.
Here's some possible theories:
- There is a live axle, Cobra motor (something obvious, like the S/C 5.4) running around. It may be an engine mule to test cooling and low speed performance -- in which case a GT-based mule would do just fine. So, it may be part of the development for the Cobra, but that doesn't mean that the Cobra will necessarily have a live rear.
- There may be plans (or prototypes) for a live axle car with an upgraded motor -- which could be the SE everyone is waiting for instead of the Cobra. Perhaps we've stumbled on early evidence of the next Mach or Boss.
- With Shelby now involved with Ford, perhaps the Cobra will have a live axle and move down to be the SE, which the Shelby Mustang becomes the top dog (with an even-stronger motor and IRS). This seems less likely, but not impossible.
- If Ford replaces the GT supercar with something like the Shelby GR-1 concept, and prices it against the Viper, it may decide to move the top Mustang down a notch and orient it more towards power. This too seems less likely as there is lots of room for a M3 beater and a Viper competitor.
Food for thought -- there's likely more information out there that will soon begin trickling in!
That's how these rumours start -- someone sees a mule or stumbles on plans and figures they've seen the next Cobra. Maybe they've seen something real, but drawn the wrong conclusions.
Here's some possible theories:
- There is a live axle, Cobra motor (something obvious, like the S/C 5.4) running around. It may be an engine mule to test cooling and low speed performance -- in which case a GT-based mule would do just fine. So, it may be part of the development for the Cobra, but that doesn't mean that the Cobra will necessarily have a live rear.
- There may be plans (or prototypes) for a live axle car with an upgraded motor -- which could be the SE everyone is waiting for instead of the Cobra. Perhaps we've stumbled on early evidence of the next Mach or Boss.
- With Shelby now involved with Ford, perhaps the Cobra will have a live axle and move down to be the SE, which the Shelby Mustang becomes the top dog (with an even-stronger motor and IRS). This seems less likely, but not impossible.
- If Ford replaces the GT supercar with something like the Shelby GR-1 concept, and prices it against the Viper, it may decide to move the top Mustang down a notch and orient it more towards power. This too seems less likely as there is lots of room for a M3 beater and a Viper competitor.
Food for thought -- there's likely more information out there that will soon begin trickling in!
Tone's idea about a live axle Cobra drivetrain test mule would make a lot of sense, perhaps that's what someone saw and overdrew some conclusions from that.
As for his other thought that there might be a big motor, but sub-Cobra, live axle model could make sense too - can we say 3V 5.4 Mach I perhaps? The Mach I being more narrowly focused towards drag strip type straight line performance, that would make a lot of sense in terms of a simple, big motor and live axle.
I would doubt that the existance of a Shelby GR-1 type supercar would push the Cobra very far downmarket, certainly not enough to start penny-pinching and compromising on overall road performance and dynamics by retaining a live axle design. There's still a yawning performance car gap between a $30K Mustang GT and a perhaps $89k+ for a GR-1.
Again, while a good live axle design can achieve very similar performance results on smooth surfaces such as drag strips, many road courses and whatnot, they cannot maintain that performance lumpy real-world road conditions and also exact a more punishing ride for a given level of performance as compared to a good IRS design. While buyers of the cheap Mustang GT might well accept that ride/handling compromise in the name of affordability, those buyers playing in the more rarified air of $40K+ performance cars are going to rightly demand much more, as the Cobra's competition is delivering.
My wild-**** prognostications would see perhaps three more Mustang models:
Mach I - 5.4 3V motor *** live axle aimed at the drag strip and stop light racing.
"Boss" 4.6/271 - 4.6 4V motor *** IRS aimed at the road course, slalom and back road warriors.
Cobra - SC 5.4 4V *** IRS with all the performance and comfort bells and whistles for the Uber Mustang crown on all performance venues.
As for his other thought that there might be a big motor, but sub-Cobra, live axle model could make sense too - can we say 3V 5.4 Mach I perhaps? The Mach I being more narrowly focused towards drag strip type straight line performance, that would make a lot of sense in terms of a simple, big motor and live axle.
I would doubt that the existance of a Shelby GR-1 type supercar would push the Cobra very far downmarket, certainly not enough to start penny-pinching and compromising on overall road performance and dynamics by retaining a live axle design. There's still a yawning performance car gap between a $30K Mustang GT and a perhaps $89k+ for a GR-1.
Again, while a good live axle design can achieve very similar performance results on smooth surfaces such as drag strips, many road courses and whatnot, they cannot maintain that performance lumpy real-world road conditions and also exact a more punishing ride for a given level of performance as compared to a good IRS design. While buyers of the cheap Mustang GT might well accept that ride/handling compromise in the name of affordability, those buyers playing in the more rarified air of $40K+ performance cars are going to rightly demand much more, as the Cobra's competition is delivering.
My wild-**** prognostications would see perhaps three more Mustang models:
Mach I - 5.4 3V motor *** live axle aimed at the drag strip and stop light racing.
"Boss" 4.6/271 - 4.6 4V motor *** IRS aimed at the road course, slalom and back road warriors.
Cobra - SC 5.4 4V *** IRS with all the performance and comfort bells and whistles for the Uber Mustang crown on all performance venues.
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Originally posted by CanadianStang@November 8, 2004, 2:16 PM
Just heard that the new Cobra, will NOT have an independent rear suspension as prevoiusly thought, and that the new Cobra will keep the solid rear axle, as the new '05 mustangs have.
Just heard that the new Cobra, will NOT have an independent rear suspension as prevoiusly thought, and that the new Cobra will keep the solid rear axle, as the new '05 mustangs have.
So many topics start with "just heard" or "heard a rumour"
Heard from who? Any way to verify? Any reliable source?
The 2005+ mustangs have to be the car that the most false rumours have come about ever. Just because you hear something from a message board doesnt mean its true. People are never able to post verifiable links other than some ******* dealer in the middle of nowhere. 99.9% of mustang fans know more about the mustang than any dealer does.
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I can see where someone heard someone else say, "The new Cobra won't have the '04 Cobra IRS." and misunderstanding it as, "The new Cobra won't have IRS." That's the problem with "I heard from a guy who heard...".
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From: Greenfield, WI
Originally posted by sharpie@November 8, 2004, 2:33 PM
I doubt that'll happen. Ford isn't going to work so much on their top performance car (going after the Vette, in their words) to place an outdated suspension in the car. Although updated, the Mustangs live axle is really unheard of in most vehicles these days, especially sports cars.
I doubt that'll happen. Ford isn't going to work so much on their top performance car (going after the Vette, in their words) to place an outdated suspension in the car. Although updated, the Mustangs live axle is really unheard of in most vehicles these days, especially sports cars.
Automobile Mag rumored the IRS Cobra's market is targeting $50 to $60 grand sport sedan/coup arena. HP is exciting, torque is fun but if you can't take a corner it ain't worth a crap! JMHO
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Originally posted by JETSOLVER@November 8, 2004, 6:19 PM
I seem to recall reading a comment from our chief engineer that they had already designed a lighter IRS for the 05 when feedback lead them to can it in favour of the solid. Thus leading to a "state-of-the art solid suspension". For what it's worth I have a 97 SVT without and it is waiting for a 99 up IRS. I have already put $ away for the next and I don't care as long as I can drive it like it out to be.
I seem to recall reading a comment from our chief engineer that they had already designed a lighter IRS for the 05 when feedback lead them to can it in favour of the solid. Thus leading to a "state-of-the art solid suspension".
For what it's worth I have a 97 SVT without and it is waiting for a 99 up IRS. I have already put $ away for the next and I don't care as long as I can drive it like it out to be.
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Perhaps IRS will be an option on the Cobra, so us drag race guys can run slicks with the new excellent SRA with strength upgrades (that everyone though was impossible) and not grenade IRS parts all over the drag strip, and save a couple grand at the same time.