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Forged Internals?

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I heard that the internals of the GT500 weren't as tough as the 03-04 Cobra's, and that it didn't come with forged internals? But then I visited http://www.svt.ford.com/ and the 'about' tech writeup mentions forged internals?


So which is it?


Also how much power is the GT500 good for? I heard 03-04's could handle tons of power due to their internals, is the same true for the new Pony's?


Just curious, anyone know?


From the site:


Just as the big-block GT500 from 1968 was a step up from the GT350, the 2007 Ford Shelby GT500’s 5.4-liter V-8 is a step up from the 4.6-liter V-8 used in the last SVT Mustang Cobra. Not coincidentally, the 2007 Shelby GT500 sports the largest-displacement engine installed in a volume version of the Mustang since 1973.


While the 5.4-liter V-8 block, overhead cams and four valves per cylinder contribute significantly to horsepower capability of the GT500, adding a supercharger and intercooler are the icing on the cake. In fact, the configuration is similar to the Ford GT supercar, offering the right combination of classic Ford big-block power and modern technology. Using the Ford GT as a blueprint, SVT has given the GT500 more total horsepower than any factory Mustang in the car’s celebrated history: 500!



Using the stout cast-iron, 5.4-liter Triton V-8 as a starting point, the Shelby GT500 employs a Roots-type 8.5-pounds-per-square-inch Eaton supercharger and water-to-air intercooler to help it produce a broad torque band on its way to making a stout 480 foot-pounds. Adding forced-induction power is more than just a bolt-on proposition. The engine’s internals need upgrading for the sake of strength and durability. To that end, the Shelby GT500’s powerplant benefits from unique connecting rods and forged pistons to handle the extra strain on the lower end of the block.

The all-new intake manifold helps to channel the supercharged fuel-air mixture into the cylinders. The unique low-profile manifold design also effectively packages the entire induction system under the GT500’s special air-extractor hood. Fuel comes from a dual-bore electronic throttle body borrowed from Ford’s 6.8-liter V-10 truck engine program.



While supercharging is a key element in the Shelby GT500’s ability to generate so much power, another major contributing component is the unique design of cast-aluminum, four-valve cylinder heads sourced from the Ford GT supercar. Machining changes have been incorporated into the outside ends of the heads and to the left rear cam cap to fit the engine into the Mustang chassis.

Developed specifically for supercharged applications, these high-performance heads use high-flow ports and specially calibrated dual-overhead camshafts to deliver optimum engine “breathing” along with surprisingly good fuel efficiency and emissions.



To enthusiasts, the real beauty of any performance car rests with its engine. That idea certainly wasn’t lost on Carroll Shelby, because Mustangs that bore his name have traditionally brought his unique sense of style and personality directly into the engine compartment. One longstanding Shelby signature feature – special finned-valve covers embossed with “COBRA Powered By Ford” – soon became the envy of so many Ford V-8 owners over the years.

The GT500 is equipped with special “Powered by SVT” finned-cam covers to hint at the beauty of all those horses lurking in the engine below. Mated to the Ford GT 4-valve cylinder heads are unique exhaust manifolds that help to better scavenge spent gases out of the cylinders and into the custom-tuned mufflers and dual-exhaust system.

To manage heat produced by those 500 horses, SVT engineers devised a set of GT500 specific features, including an air-extractor hood, a high-capacity aluminum radiator, an intercooler mounted below the blower, a loop-style power-steering cooler and an oil-to-water stacked-dish engine oil cooler.  



The gearbox used in the 2007 Shelby GT500 also is a rarity. Few transmissions exist in the marketplace today that can handle the torque loads generated by the supercharged GT500 V-8, so engineers have opted to stick with the proven heavy-duty performance of the TR6060 6-speed manual gearbox.

The GT500 employs an upgraded version of the T-56, which first appeared in the 2000 SVT Mustang Cobra R, powered by a naturally aspirated 5.4-liter V-8 with 385 horsepower, and later in the supercharged 2003 SVT Mustang Cobra whose DOHC 4.6-liter produced 390 horses. For the Shelby GT500, the six-speed manual is geared to make the most of the supercharged 5.4-liter’s broad power band.


Fords' “MOD” V-8 family of engines make more power than anything out of the factory in the past, yet tops 20 mpg on the highway and still meets the government's LEV-II tailpipe emissions standards.



A major goal set for the Shelby GT500 was to take Mustang handling to the next level. Ford Special Vehicle Team chassis engineers worked to deliver a whole new set of standards worthy of the Shelby GT500 name.


The GT500 retains the same Mustang suspension setup that helped the Ford Racing FR500C win the 2005 Grand-Am Cup championship and claim the manufacturer’s title for Ford. The front features coil-over MacPherson struts with reverse “L” lower control arms made of lightweight I-section steel.  In the rear, there’s a three-link live axle with coil springs, Panhard rod, outboard shocks and stabilizer bar.


Despite its bigger engine up front, the Shelby GT500 retains neutral handling thanks to the use of stiffer stabilizer bars. In addition, the rear bar is larger than that of the Mustang GT. The GT500 uses a 34-millimeter tubular front stabilizer bar. Coupe versions of the GT500 sport a 24-millimeter rear bar, while convertibles come with a 20-millimeter bar.



A true performance car stops as well as it goes. To that end, the Shelby GT500 features Brembo front brakes with big, four-piston calipers and vented 14-inch discs. In the back, GT500 utilizes the Mustang GT’s 11.8-inch vented single-piston caliper rear-disc setup with unique pad material. Both Coupe and Convertible models ride on four 18-inch x 9.5-inch aluminum wheels, wearing 255/45ZR18 tires on the front and larger 285/40ZR18 tires on the rear.


To improve steering feel, the GT500 adds a brace that connects the rear lower arm bushings side to side. For added precision, a special steering pump is used, and the steering gear utilizes a unique torsion bar.

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unique connecting rods and forged pistons


Supposedly, the forged pistons are "stronger" than the Terminators, it's the rods that are a "weak point".


*** I make no claim of superior knowledge about the correctness of "stronger" and "weak point" - these are just what most are posting about the GT500 vs. the '03-04's. ***

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I've heard above 720 crank HP is in the danger zone or getting close to it with the stock rods. The terms had their issues too but the rods were not one of them. As for crank to RWHP people are using 14-16% for what is lost from the crank to the wheels usually.

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As they said in an article I read online recently "there's no such thing as a safe-point" there's only broken, not-broken and rates of wear. ;-)


That said, the internals of the GT500 are definately forged: forged aluminum pistons, forged cracked-powder I-beam rods, forged crank.


The Termies were tough and their Manley H-beam rods have a great reputation and Ford used H-beams in the Ford GT (Mahle) as well, so when Ford went with the forged cracked-powder I think many wrongly assumed that Ford 'cut corners' to save expense. I think, instead, they chose that tech because they are very strong under compressive loads though not likely as strong as the Manleys and Mahles in tensile strength. I suspect Ford did that because the higher piston speeds and more excessive rod angles of the 5.4 make limiting revs to 6250 prudent to begin with, whereas the 4.6 geometry has equivalent piston speeds at about 6800 rpm. So the forged cracked-powder I-beams are a good match for a blown motor not seeing much over 6000 rpm where compresive loads are the primary concern and are likely just as strong as the H-beams, possibly stronger, on compressive loads.


So, how much is toomuch for this motor? There is no 'cut-off' point... but I'm told Ford did extensive testing at 650crankHP and other some seem to think it's pretty solid to 750crank. I suspect that's probably true with a 'safe' tune (<lol> there's that word again) and sifts at 6K with the rev-limiter set at 6200 -- but there is no "safe."


Is the GT500 'safe' with Evo stage-II? Safer than with stage-IV. Is it 'safe' with stage-IV? Safer than the KB at 18# <lol> My feeling is that stage-II or IV is rather safe if the revs are managed, you know how to shift, and you're carefull to not make it a habit of bouncing off the limiter, especially with a cold motor. Will it wear faster than stock with such mods if your right foot is using them frequently -- surely. Is it that big a deal? Likely not if your car is meticulouly maintained, your prudent and run street tires.


On the other hand, let's face it, stage-IV @ 630rwHP with drag radials, rev-limiter off, and 6500 rpm power-shifts and you're playing Russian scrap-metal roulette! But at similar piston speeds and proportional output, the same would be true with a Termie, imo.


<ok, fire-away... napalm suit on -- lol>



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Interesting, thanks for the post!


I was surprised that you mentioned a low shiftpoint? Every Cobra I have owned shifted at almost 7000 RPM's, where does the GT500 shift?


Thanks again,




I think it's rated at 6,000 in the specs with the factory rev-limiter set at 6250 (according to what I've read). Ford recommends that the rev limiter is not bumped -- good advice, I think for the reasons above, but also because this motor's torque curve is so flat and broad, there's no real gain in pushing shifts beyond 5800-6k, imo.

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I think it's rated at 6,000 in the specs with the factory rev-limiter set at 6250 (according to what I've read). Ford recommends that the rev limiter is not bumped -- good advice, I think for the reasons above, but also because this motor's torque curve is so flat and broad, there's no real gain in pushing shifts beyond 5800-6k, imo.



I would agree with this. I've been watching and in spirited driving I find shifting is around 55-5800 usually as I drive more by the sound and feel of the car than the shift light or the tach. I've set my limiter back to 6200 and have only once come close to that (in 3rd when playing with a sport bike). Even then I was shifting at 6K. The torque is dropping as you get over 5K and the shift puts you right back in the power band. It's actually quite impressive how hard the car pulls all the way through each gear when driving it.

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  • 6 years later...

i want to know if anybody did this, ill have to refer to van, but i just want to beef up the rods so i can go to 6700rpm. if theres anything else i need to install ill find out but how much would this cost to install

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