S550 Mustang Suspension and Powertrain Discussion

[kcbrown]

Sitting over here on 315 A6's and stock power, thinking "I need more tire"

If you can make the car break traction in the corners, then you need more tire.

 

[Norm Peterson]

Based on having worked for an OEM at one point and an interview I saw with Hameedi about the '13 GT500 when it came out, the reason for the narrower than needed tires for actual performance is the negative steering characteristics (I.e. Pull in grooves). Hameedi said they didn't put larger tires on the GT500 because, after trying that, they didn't think the average buyer who doesn't track their car would want to deal with the steering characteristics.

The GT500s have always had 9.5" wide front wheels, with 255/45-18's on the earlier cars and 265/40-19's on the later ones. You'd think those setups would have had to meet similar scrutiny, and that a setup with 19x9.5's and 265/40's at all four corners could have been a no-brainer.


There were no adverse effects when I went from 235/50-18 KDWS's on the OE 18 x 8.5" wheels up to a set of 18 x 9.5" FRPP/GT500 wheels and 255/45-18 tires at all four corners, not even a deterioration in ride quality that I ever noticed (1st gen Goodyear Asymmetrics, if that matters). I already did have the Konis and aftermarket sta-bars on the car, but changes to those things from base GT spec aren't outside what a PP could reasonably include.

I will give you that something like 285/35's on wheels out at or at least near max-recommended width will provide a ride that's too hard for many, but I'm still not experiencing any issues with directional control/stability (PSS on 18 x 11's all around). It's occurring to me that the recent complaints against the 1LE Camaro's ride might be mostly a consequence of the tire size and wheel widths rather than suspension calibration.

Here's the thing, the Brembo and Track Pack Mustangs sold very well and you know what most owners did with the factory summer tires? Replaced them. I don't recall people having some big up-roar about having to do it either. I Figure most people sucked it up as they accepted they bought the performance version.

More useful than simply knowing that people replaced the factory summer tires would be knowing what they replaced them with, and why. Tire make, model, size(s), and a reason. It's probably safe to discard any cases involving Nitto NT555's or BFG Radial TA's.


Norm

 

[Pentalab]

The GT500s have always had 9.5" wide front wheels, with 255/45-18's on the earlier cars and 265/40-19's on the later ones. You'd think those setups would have had to meet similar scrutiny, and that a setup with 19x9.5's and 265/40's at all four corners could have been a no-brainer.
Norm

For the rwhp / rwtq that your typ oem 07-12 GT-500 makes, imo, a 265 rear tire is way too small... and unuseable on a 13-14 GT-500. 10" + 275/285 fronts....and 11.5" + 315 rears would have made more sense...albeit a staggered setup.

For an oem square setup, 10" + 285's would work well. Roush has been using a square 10" + 275 config for yrs now. Toss a blower into the mix, and the 275 rears are marginal.

 

[BMR Tech]

Should have some spring rates from the PP model soon, as well as dyno for the rear shocks.

I am learning quite a bit about these cars.

 

[Department Of Boost]

We tore ours APART yesterday. The entire front end is off the car and the motor is stripped down to the longblock but with no intake on it. And when I mean entire front end, I mean entire front end. No hood, no fenders, no bumper cover, etc. Ford did some really nice stuff with the S550. The aero is awesome! All the little details are amazing.

Working on a manifold with a HUGE IC right now and a HUGE HE.

 

[BMR Tech]

^ Nice!

Did you happen to measure the driveline angles?

It appears that Ford designed these with a -3 engine angle, and +3 pinion angle from the get go. (engine down 3, pinion up 3 - zeroed out)

 

[Department Of Boost]

^ Nice!

Did you happen to measure the driveline angles?

It appears that Ford designed these with a -3 engine angle, and +3 pinion angle from the get go. (engine down 3, pinion up 3 - zeroed out)

We didn't get anywhere near the rear end of the car. That will probably be a few months (snowing here, no hurry).

Did your non PP car come with the V brace that goes from the strut towers to the firewall? Our PP has it, and I think I have seen some non PP cars that have it. But people are saying it only comes with the PP cars. IDK what the story is.

We have some really big bracing on the chassis behind the inner fenders behind the wheels up front too. I wonder if they all have that.

After messing with the car I see where the extra weight came from, and that it would be easy to take it out for a street strip car. And Ford did a lot to trim things down in other areas. I suspect all prepped up the car could be quite a bit lighter. It would loose that "BMW" feel though.

 

[BMR Tech]

My Non PP Car does not have that.

 

[Department Of Boost]

Check this beast of a brace out

 

[Department Of Boost]

My Non PP Car does not have that.

Isn't this it right here? Or is that the plastic bulkhead that goes between the battery and the engine compartment? It's hard to tell in the pic.

Of course there isn't one on the DS though. I haven't figured out if that is one piece yet.

 

[BMR Tech]

It is plastic.

 

[BMR Tech]

That brace is interesting...

I wonder how much of a brace it is, and how much of a protector for something it is?

 

[csamsh]

Should have some spring rates from the PP model soon, as well as dyno for the rear shocks.

Want to see that- Ford claims monotubes...

 

[Department Of Boost]

Want to see that- Ford claims monotubes...

They may be, the PP cars feel like there is something really good going on in there. Real good low speed compression but not "kick you in the tail" high speed. And the rebound is really, well, there. Which is unusual for OEM stuff.

They will most likely be junk by 15K miles like every other OEM damper though.

 

[claudermilk]

Wow, you're not messing around. No pics? Also waiting on the "how much does X weigh?" posts. You know they're coming.

 

[NDSP]

Just the specs:

5.2L Flat Plane Crankshaft V8 Engine
More than 500 HP / Torque Peak above 400 lb-ft
MagneRide dampers
Brakes: 6 piston brembo calipers front / 4 piston brembo calipers rear
19" aluminum wheels - 10.5 front / 11 inch rear
Michelin Pilot Super Sport tires w/ GT350 specific sidewall construction, tread and compound
Torsional stiffness increased 28% over previous model
Cutting edge injection molded carbon fiber composite grille
Optional lightweight tower-to-tower brace
Unique Sheetmetal
Cloth Recaros

 

[fdjizm]

I'm not going to lie, it moved a little.

 

[claudermilk]

Just the specs:

5.2L Flat Plane Crankshaft V8 Engine
More than 500 HP / Torque Peak above 400 lb-ft
MagneRide dampers
Brakes: 6 piston brembo calipers front / 4 piston brembo calipers rear
19" aluminum wheels - 10.5 front / 11 inch rear
Michelin Pilot Super Sport tires w/ GT350 specific sidewall construction, tread and compound
Torsional stiffness increased 28% over previous model
Cutting edge injection molded carbon fiber composite grille
Optional lightweight tower-to-tower brace
Unique Sheetmetal
Cloth Recaros

FINALLY looks like decent tires getting mounted, too.

 

[RazorbackMustang]

Don't forget 15.5" front rotors and 15" rear rotors!

 

[Department Of Boost]

This thing better be about $55K. No way it can sell for $75 with those specs.

I was hoping for carbon brakes and more power. I'm not interested enough to spend my $$$ on it. Looks like back to plan A, a S197 track car. Maybe a used BOSS 302S or FR500. Or just build something.