JIM5.0

True, the majority of us who buy the GT, or the even fewer and luckier ones of us who buy the GT500 (or Cobra, or GT350, or whatever the S550 top trim will be called) don't care too much about MPG.

Surprisingly, FoMoCo has always done very well wit the fuel economy of the GTs and even the GT500. The current 2013-2014 662BHP Trinity GT500 still get above 20MPG and does not have the Gas Guzzler tax slapped on it.
I daily drive my GT, a 2011 with only the 412BHP Coyote with 3.31:1 rear gears, and I see above 30MPG on long flat 70MPH freeway trips.
Even at 85MPH, I hit an MPG Avg of 22-24MPG.

Even though we Mustang fans could care less about fuel economy, C.A.F.E. regulations of that dog-gone EPA still forces Ford's hand to make even our V8s fuel efficient.

Brian@Vossen

Do you guys think the extra weight is worth having with the independent rear suspension or do you think the live rear axle would of been the better route?

Derf00

On a global platform (what the S550 generation of mustang is about), it's all about MPG. How good, or bad it does in the global market will redefine the next gen after the S550 or if the mustang will even exist after the S550.

The U.S. has always lagged behind most other 1st world countries when it comes to giving a chit about anything other than (our) personal preference.

Derf00

All depends, if the weak point in the drivetrain is the half shafts (like it was on the vette), then no, it will not be worth having the IRS. I think its fine in general though.

MustangInTexas

So you really think that Mustang's future depends on what it does overseas? The US sales will remain the vast majority of Mustang sales. Other markets are nice but don't expect them to take over. Original sales numbers will be high because many people will want one - pent up buying and all. But in the long run, the US sales will determine the future of the Mustang.

jz78817

you can really tell the difference, especially on uneven pavement. on a track the live axle of the S197 isn't a liability, but on the street it really does clomp and jiggle around back there.

Brian@Vossen

I agree. When riding around in my friend's mustang you can tell when just driving normally. In my opinion I think the IRS is an awesome upgrade for the new S550.

Genxer

If the IRS adds a few pounds then maybe we will see better weight distribution figures. Ford redesigned the front suspension to be on par with the improved rear too. It could be a really nice, balanced car especially with the turbo 4.

JIM5.0

Not just the 'Vette, but also the current Camaros too. The 5th Gen Camaros are only 420 ft-lbf crank torque and they can twist their half-shafts to damage.
To address this, the Camaro SS now has a 1LE package with superior half-shafts to virtually eliminate this problem.

The S550 GT will only be 400 ft-lbf crank torque, but add some bolt-on mods and a tune and the stock half-shafts will not survive long.

I too think the S550 half-shafts will be fine on stock BHP and stock tune, but it will not be long before modders push serious BHP from the new S550 Coyotes to find the failure points of the stock half-shafts.

JIM5.0

I agree here. The S550 is designed for Europe. Sure, it will get sold in other non-Euro countries too, but the key design upgrades of the S550 are clearly Euro.

I do not have a clue how well the S550 will do in the Euro market; but if FoMoCo wants to sell it like hotcakes in Europe, Ford had better begun to do very heavy marketing there. Otherwise, all the massive amounts of money to R&D the S550 will have been wasted.