What is this thing in '13 shelby gt500?

[LimaCharlie]

Just to clarify, this is the back of a Boss 302 Laguna Seca. The regular Boss 302 has a back seat. The brace is used to solidify the rear axle of the Mustang.
I think this is a popular upgrade for all the new Mustang's, V6 through GT500, because it can bolt in.

[eolson]

It is a direct solution to the fixed axel "Monocoque" problem where the inner rear wheel lifts in hard corners. This cross brace greatly reduces that effect and loss of traction grip in corners. Gt500 needs one badly, as well as a watts link. Erik

[MYDLIFECRISIS]

Originally Posted by SeanSandoval

Flux Capacitor

[ec1990]

Originally Posted by Ry_Trapp0

can you explain this further? i've seen you post about this MANY times over the past year or two but have yet to hear a complete explanation as to what you're referring to. examples of S197 mustangs lifting the inner rear wheel would be appreciated as well.

The Mustang has a solid rear axle so the rear wheels are directly connected so if one wheel has to drop down further, say in a turn, the opposite rear wheel lifts up. This is different in an independent rear suspension such as in the Camaro, where each wheel has its own distance of travel. In the Camaro if one wheel drops further the other wheel does not have to compensate for that drop with lift, each wheel acts independently. Look up solid rear axle vs. independent rear suspension, the basic difference is whether the wheels act independently or do they act dependently where a drop/lift on one wheel causes the opposite wheel to lift/drop.

[midnighter]

That looks like the Continuum transfunctioner to me.

[VRYALT3R3D]

.......lol

[He11bent]

Originally Posted by Ry_Trapp0

lol, c'mon now, lets pretend that i may have been around a few cars in my life.
having said that, first i gotta ask about the bolded statement. when you say "lifts up" are you saying that it literally lifts the inside rear tire off the ground? if so, i would be REALLY interested in seeing some examples of solid axle cars lifting the inside rear tire. i can find plenty of examples of IRS cars lifting the inside rear tire - mainly FWD race cars with full cages and REALLY stiff rear sway bars.
second, i have to disagree with you about how one tire affects the other on a solid axle(a 3 link, 4 link, torque arm, or similar solid axle suspensions anyways). one tire lifting over a bump or drooping into a dip doesn't cause the other tire to do the opposite. the other tire simply maintains its current position along the Z-axis, so long as it doesn't encounter a bump or dip of its own(though its contact patch is obviously affected by the opposite tire as it moves along the Z-axis). now, a single pivot tractor axle will act the way you described...

...but that's simply because it's designed to pivot around a central axis, while the 3 link w/ panhard on an S197 mustang isn't.

finally, what does this have to do with the aforementioned "monocoque problem/effect" and how an X-brace in the rear bulkhead fixes this?

do you REALLY drive a Geo Metro with Nitrous?

[MEDISIN]

Originally Posted by Ry_Trapp0

now, a single pivot tractor axle will act the way you described...

So that's where Ford found the suspension design for the Mustang

[MEDISIN]

Originally Posted by pdari

it is what I wish the 1LE has instead of back seats.

I don't know that it's necessary (experts can chime in). Take the CTS-V for example, the sedan has fixed rear seats for extra ridgity but the V coupe's seats fold down. Here's a post from marktanner at CadillacForums that summarizes:

Back in '08 and '09, numerous articles on the V mentioned that the folding seats were specifically excluded due to structural issues with the extra stresses of the added power of the V2. The solid rear seat and bracing helps to maintain rear suspension geometry under extreme loads, and was mentioned as an example of the extra care in engineering of the car. Of special interest is the fact that, while folding rear seats are readily available on the regular CTS sedan, it's not available with the Recaro option, because that seat has the Alcantara inserts, and was engineered originally for the V. The wagon obviously lacks these issues, as the seats cannot really be structurally attached to the car, and the coupe's structure apparently doesn't need the added bracing; probably has to do with fewer openings (doors).

I know the V and Camaro are different platforms (Sigma II vs Zeta II), but I understand they are also very similar. Even the ZL1 has folding rear seats so it must not be a power issue.

[Tob]

Originally Posted by eolson

It is a direct solution to the fixed axel "Monocoque" problem where the inner rear wheel lifts in hard corners. This cross brace greatly reduces that effect and loss of traction grip in corners. Gt500 needs one badly, as well as a watts link. Erik

Can you further define axle monocoque? The phraseology you are using is incomplete at best. If you are referring to the term as "used to indicate a form of vehicle construction in which the body and chassis form a single unit" (Wikipedia) then one would assume you are simply referring to the unibody construction style that Ford has chosen for the Mustang and that GM has chosen for the Camaro (among others).

In the context of "monocoque" (your usage) there is an implication that in a production style (unibody) vehicle that the strength resides in triangulated, boxed, or bulkheaded sections. With respect to Ford's decision to add an 'X' style brace to what is normally the rear seat area, can you provide any tech or data that clearly shows how "this cross brace greatly reduces that effect and loss of traction grip in corners"? Have you ever measured the amount of body/chassis deflection in this specifc plane on an S197 chassis while being driven either aggressively on the street or road course?

Regarding how badly the GT500 needs a Watts Link, can you explain whether or not it is beneficial to exploit the asymmetric behavior of a panhard bar versus any geometrical benefit to a theoretical fractional reduction in the lateral migration of the rear axle housing relative to the body that is offered by a switch to a Watt's?

Care to comment on the following comment by Jack Hidley of Maximum Motorsports?

With regards to the PHB versus Watts link, the roll couple of the suspension with a PHB is more constant than with a Watts link during ride height changes (assuming the Watts bellcrank mounts to the differential). With the Watts link, the roll center stays at a fixed height as the cg moves up and down. With the PHB, the roll center moves up and down somewhat as the cg does. This gives the PHB an advantage on a course with hills. The minute difference in lateral axle movement between the two has nothing to do with the handling differences, in my opinion.

[OffseT]

Originally Posted by kenkartasasmita

so i saw this this on the new shelby gt500. does anyone know what is it? and why we dont have one?

Rear seat delete kit... If your remove the rear seats you have access to the trunk from the front seats. Put this in and it fill sin the whole. Only advantages are weight reduction.. nothing to do with the chassis

[Fenderaddict2]

Originally Posted by SEVEN-OH JOE

Unlike the BOSS LS, the 1LE doesn't NEED such a reinforcement. And the 2-seat BOSS LS weighs 5 lb MORE than the 4-passenger BOSS because of it.

That's not why it weighs more. It's why it's only 4 lbs more. Bring added rigidity to the chassis already bolstered by larger rims, tires, sway bars, splitter, brake ducts, trans scoop and spoiler.

[SEVEN-OH JOE]

1/2" wider rear 19s add 1 lb each (according to ARE). Tires are a wash. Ducts/cooling scoop must add all of 5 lb, as does the splitter and spoiler (each). 1mm bigger rear bar adds about 1lb.

Now, just how heavy is that 20 lb. or so rear seat? Compared to that steel tubing X-brace and molded surround? Which weighs more than the 5 lb Curb difference. My original point.

Boss = 3631 Curb
Boss LS = 3636 Curb, according to Ford (argue with them).

Hair now fully split.

Ordered your ZL1 convertible yet?

[TheReaper]

Originally Posted by Tob

Can you further define axle monocoque? The phraseology you are using is incomplete at best. If you are referring to the term as "used to indicate a form of vehicle construction in which the body and chassis form a single unit" (Wikipedia) then one would assume you are simply referring to the unibody construction style that Ford has chosen for the Mustang and that GM has chosen for the Camaro (among others).

In the context of "monocoque" (your usage) there is an implication that in a production style (unibody) vehicle that the strength resides in triangulated, boxed, or bulkheaded sections. With respect to Ford's decision to add an 'X' style brace to what is normally the rear seat area, can you provide any tech or data that clearly shows how "this cross brace greatly reduces that effect and loss of traction grip in corners"? Have you ever measured the amount of body/chassis deflection in this specifc plane on an S197 chassis while being driven either aggressively on the street or road course?

Regarding how badly the GT500 needs a Watts Link, can you explain whether or not it is beneficial to exploit the asymmetric behavior of a panhard bar versus any geometrical benefit to a theoretical fractional reduction in the lateral migration of the rear axle housing relative to the body that is offered by a switch to a Watt's?

Care to comment on the following comment by Jack Hidley of Maximum Motorsports?

Thanks for asking these questions.