Justin: Hey, guys. Justin with AmericanMuscle.com, here at the Stage 3 Power Pack Bolt-On Build-Up for all 2013 and '14 GT500s. What we've learned over the course of these first two power packs is that these cars are huge overachievers right from the factory. We also learned they respond incredibly well to mods, picking up huge amounts of power, even with the most basic bolt-ons like we saw in the Stage 1 Power Pack.
But we also learned that these cars tend to run out of breath pretty quickly, especially when those power and boost levels start increasing. So in the Stage 3 Power Pack, we installed a few mods onto our '14 GT500 that should help it breathe a lot easier in the quest for laying down 700 wheel horsepower. But before we get started, just wanna remind you guys to subscribe to our YouTube channel, if you haven't done so already, for more bolt-on build-ups, some of our product overviews, and, of course, more project cars.
One of the biggest bottlenecks on any car is the factory catalytic converters. Now, even though Ford did a great job in designing some pretty high-flowing cats here for the '13 and '14 GT500, for the purposes of our power pack, they just had to go. In its place now is the stainless steel 2 and 3/4-inch off-road x-pipe, which does, of course, eliminate those factory cats, greatly improving our exhaust flow.
Helping us achieve that more aggressive tone, we installed the Axle-Back from Kooks Performance here. This is the Kooks Performance Axle-Back Exhaust System with the quad tips in place. Now, don't get me wrong. I'm a huge fan of the factory GT500 exhaust from the looks down to the tone. But what Kooks has done is actually use their 40-plus years in the exhaust field and improved upon the factory design. We're looking at a 3-inch oval race muffler with the dual 4-inch polished tips, giving it that signature GT500 look. Now, this axle-back, paired with that off-road X-Pipe, just produces an exhaust sound that is totally evil. In fact, listen for yourself.
Now, with everything taken care of with the exhaust, let's move to the intake here, where we saved the best for last. Now, when I say the best, in this case, is the throttle body, a lot of you guys are probably gonna go, "Really?" But the truth is upgrading the throttle bodies on these '13 and '14 Shelbys usually yield massive results, and at this point in our build, it's pretty much become a necessity. The lower balancer we installed in Stage 2 has increased our boost by spinning our TVS blower much faster, while the JLT Big Air Intake here has essentially let more air into our motor.
However, the only thing standing between those two parts, the supercharger and the intake, was the factory throttle body, basically causing a massive bottleneck. In its place now we have a huge upgrade, the Ford Racing Super Cobra Jet Throttle Body. This is actually the same throttle body used on the purpose-built Cobra Jet drag car, so we know it's proven. It's designed to replace the twin 60-millimeter stocker with a massive mono-blade oval design, which actually outflows the twin 65-millimeter throttle body from Ford Racing by a couple hundred CFM. Since it is built by Ford Racing, of course the quality, electronics, and fitment are all completely dead-on, as you might expect. And best of all, it's really gonna uncork the air flow entering our Trinity motor.
With all of our Stage 3 mods in place, we're gonna get Mike J. in here from the Bama Performance team to talk a little bit more about what we did and, more importantly, get a much needed tune for our Shelby. All right, Mike, as you and I were talkin' about, man, the whole theme for this power pack was just helping our '14 breathe a lot easier.
Mike: Well, it definitely needed it. As we saw on our baseline runs, the car's making great power, but it's running out of breath in the upper RPM range. So when you add a throttle body, you add exhaust, we're really gonna see improvements there.
Justin: Awesome, man. Now, we know these big mono-blade throttle bodies are a little tough when it comes to drivability, tuning, and all that stuff. Tell these guys how the Bama team's gonna tackle that.
Mike: A lot of dyno time and a lot of logging. And then you're right. These are key factors. Idle and part throttle drivability are probably the most key things you wanna focus in on. We did a really great job on this of nailing both of them, and then we got to play with the fun stuff, which is full throttle.
Justin: All right, speaking of fun stuff, guys, I think this thing's gonna be well over 700 at least, just around there. Mike, are you with me on that? What do you think?
Mike: I think we're gonna be right there and, if not, just a tad bit over, but I wouldn't count it out.
Justin: All right, let's do it. At the end of our Stage 2 Power Pack, our 2014 GT500 was laying down 657 horsepower and 696 pound-feet of torque at the rear wheels. With everything installed here in the Stage 3 Power Pack, our GT500 is now putting down a very impressive 709 horsepower and 727 pound-feet of torque. That gives us a peak gain of 52 horsepower over our Stage 2 numbers and gains of 65 horsepower and 57 pound-feet of torque throughout the curve. So to recap, our baseline run with our stock 2014 GT500 gave us 600 horsepower and 544 pound-feet of torque. With all three power packs installed, the car was now making 709 horsepower and 727 pound-feet of torque, giving us a peak gain of 109 horsepower over those baseline numbers and curve gains of 163 horsepower and 193 pound-feet of torque.
These power packs, featuring the 2013 and '14 GT500, show why these cars are at the top of the food chain when it comes to muscle car. That's because, honestly, for the money, there's nothing that can touch the power that these things are capable of, especially when given a little help like we demonstrated here with our power packs. We hope you guys have enjoyed the Bolt-On Build-Up for the '13 and '14 GT500. and remember, for all things Mustang, keep it right here at AmericanMuscle.com.