Mustang MonthlyHow To Engine
How to Install the Granatelli Cold Air Induction System - ’05-’10 Induction Upgrades
Cold air and a larger throttle body are good for at least 25 more horsepower
Ford’s 2005 Mustang redesign opened a new chapter of Mustang performance within an exciting new retro body style. The all-new S197 Mustang has been a great performer for a decade now and because Ford has produced so many of these Mustangs there are plenty of them to be had for not much money in GT form with the 4.6L 3V SOHC V-8 and a choice of five-speed manual or automatic.
Right off the truck the ’05-’10 Mustang GT produced an advertised 300 horsepower at 5,720 rpm and 320 lb-ft of torque at 4,500 rpm. For a box stock V-8 Mustang in those days these numbers were good for somewhere around 250-270 horsepower at the tires.
When we went to J.R. Granatelli at Granatelli Motorsports and asked him what he could do for a ’07 Mustang GT to give it a little more “go” for an enthusiast on a budget, he went into his parts department and brought out two items he believed would give us nice gains in power without selling off the farm. The Ford ’05-’09 Mustang Air Induction System, PN GM-410040-P, is an easy to install package you can drop into your Mustang’s engine bay in less than an hour. GMS also offers an induction kit for the ’10 Mustang GT under PN 410045 (add P for polished version). While you’re installing the cold air system, the Twin 62mm Bore Throttle Body from Granatelli for ’05-’10, PN GM-TB0007, installs in minutes before the cold air system goes in. The throttle body installation takes a bit of patience and close attention to the instructions in your Granatelli Motorsports kit. Without paying close attention to proper installation, you can count on drivability problems you don’t want to have. Let’s get started.
1. Removal of the factory system begins with the intake duct and air filter housing. Here, tuning professional Ray McClelland of Full Throttle Kustomz in Oxnard, California removes the duct clamp at the stock 55mm twin throttle body with an 8mm socket.
2. Next, the electrical connections for the throttle position sensor and throttle drive motor are disconnected. These connectors use a red lock tab that must be disengaged first before you can depress the release finger and slide the connector free.
3. The factory air filter housing is secured by a single bolt and two rubber isolators. The intake duct and the filter housing are disconnected and removed as an assembly.
4a-b. The stock twin 55mm throttle body is removed using a 10mm deep well socket. Do not remove the factory O-ring seal in the intake manifold inlet.
5. First to be installed is the Granatelli throttle body adaptor, which will enable you to install the larger 62mm throttle body to the factory intake. This piece is sandwiched between the stock intake and the new throttle body.
6. The twin 62mm throttle body assembly is installed using the provided fasteners in the kit and a 10mm socket. The retaining bolts are torqued in a crisscross fashion to 89 inch-pounds.
7. The throttle drive motor connector, as well as the throttle position sensor connector, are both connected at this time. Ensure the red lock tab on each connector is pushed back into the locked position too once the connectors are seated.
8. The cold air induction inlet is cast aluminum (and in the case of our kit is the optional polished finish). To connect the inlet to the throttle body an intake duct adaptor is installed and the clamp tightened using an 8mm socket.
9. The Granatelli cold air kit utilizes a heat shield for the conical filter and is installed on the left inner fender using the OE air filter housing mounting points with the new fasteners provided.
10. The polished inlet tube is fitted to the inlet adapter and the heat shield and checked for proper fit and clearance. You’ll notice the factory slot-type mass-air meter electronics have already been transferred from the factory inlet tubing to the new Granatelli part as well. The Granatelli cold air duct looks sharp and will improve air flow into our larger 62mm throttle body, which is an off-the-shelf Shelby GT 500 item.
11. The washable high-flow conical air filter is a vast improvement over the stock paper element because it delivers unrestricted air flow from outside a hot engine compartment thanks to the included heat shield.
12. This is the Granatelli mass air sensor adaptor, which is a simple connection between the OE wiring harness connector and the slot-type mass air meter that was transferred to the Granatelli cold air inlet.
On the Dyno
Tuner Ray McClelland of Full Throttle Kustomz dyno tests Glenn and Julie Eldridge’s ’07 Mustang GT/CS coupe to determine how much power has been gained with the Granatelli twin 62mm throttle body and cold air kit installation. The beauty of the Granatelli package is that a custom tune of your Mustang’s PCM is not required. Just install, plug and play. However, if you chose to add additional tuning to your Mustang even better results can be had! Baseline numbers for the ’07 GT/CS were 265 horsepower and 285 lb-ft of torque at the tires. With the Granatelli cold air induction and 62mm throttle body along for the ride, and with a solid tune from Ray McClelland, we realized a 70 horsepower gain along with 39 lb-ft of torque at the tires. Not bad considering the easy modifications we’ve made.
What we learn from the installation of Granatelli’s own cold air induction and a larger GT 500 throttle body is these items alone will make a nice little difference in power. You can expect a 25-30 horsepower increase with these easy bolt-ons if you have a healthy engine to begin with. Where this Mustang stands tall is when the Full Throttle Kustomz tune on Granatelli’s dyno is added to the mix. When Ray McClelland was finished, Glenn and Julie Eldridge’s Mustang GT/CS ran considerably stronger and has been a great pleasure to drive.