Pounder. Today s performance. Pushing a daily-beaten 07 Mustang GT from 13s to low 11s one pass at a time.

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1 Quarter- Pounder with Boost Pushing a daily-beaten 07 Mustang GT from 13s to low 11s one pass at a time. Today s performance world, especially the Mustang segment, centers mainly on chassis dyno results. Rightfully so, as these wonderful tools have helped the market in many ways. As a customer, they help you know how much power and torque is gained (or lost) from modifications performed. Chassis dyno testing also gives tuners/builders the ability to properly dial in the engine tune by re-programming the ECU or using old school methods, like re-jetting the carburetor and using a timing light. In the digital world, you cannot browse a message board without being inundated with By Michael Galimi dyno graphs as enthusiasts share their trials and tribulations in the quest for more output. This also keeps the industry honest, as customers no longer have to take the word of the manufacturer. Bone-stock, the GT clipped off a best of A DiabloSport tuner with custom JPC tune and Ford Racing Bullitt cold-air intake dropped that to at 104 mph PRESENT HOT MUSTANG PROJECTS MMFS V.indd 58 10/5/11 4:53 PM

2 Of course, we all have egos and want to have the graph with big power. For us, the real test comes on track. Leave the graphs at home there is no disputing what goes down the quarter-mile or on your favorite road course. Go from here to there as quick as you can. No spikes on the curve, generous dynos, or correction factors what happens at Englishtown relates to what happens 1 in the Texas Motorplex or a track in California. Plus, it s just more fun. With all this in mind, we set out to modify an 07 Mustang GT equipped with a 5R55S automatic transmission. It has been strapped to the chassis just once for tuning with the supercharger system. The rest of the time, we ve pounded the dragstrip using the time clocks and trap speed to determine the effects of new parts. Baseline testing went as usual. We yanked the unnecessary parts, like the spare tire, and aired the stock Pirelli tires to 40 psi. The result was a best of at 102 mph in 100-percent stock form, right down to the 3.31:1 rear gears. The addition of a tune from DiabloSport Predator lowered the times to consistent 13.50s at 103, the best being a After running 12s, we turned our attention to the looks department and added GT500 brakes and wheels. The car also wears a Steeda cowl hood and Competition front fascia. 2 A set of GT500 fuel injectors was added, with twin in-tank pumps to help supply enough fuel for the boosted 4.6L Three- Valve modular engine. 4 A Ford Racing twin-screw supercharger is intercooled and checks in at 2.3L of volume. The supercharger requires its own lubricant that should be changed between 75,000 and 100,000 miles. WINTER MMFS V.indd 59

3 5 Ford Racing supplies spark plugs that are one heat range colder than stock. We verified the gap to be inch. 6 Then we got more daring and Justin Burcham of JPC Racing loaded up a custom tune at the track once again no dyno testing so we couldn t brag about how much our GT was making. It featured a leaner air/fuel ratio, better automatic transmission functions, and a cleaned-up torque management strategy. We continually played with shift points and eventually knocked off a at 103 mph. Our next step was adding a Ford Racing Bullitt cold-air kit in the staging lanes. Burcham loaded a new tune to compensate for the increased airflow. There are some cold-air kits on the market that don t require the reflash, but the Bullitt wasn t one of them. The new tune and Bullitt intake brought us to a jaw-dropping at 104 mph on stock tires and virtually stock everything else. Some might cry foul, but in our defense, the weather was outstanding and we took advantage of it. Holding a 12-second timeslip and 7 9 The Steeda 10-rib conversion kit requires a longer snout because it uses a dedicated blower drive rather than running inline with the accessories like the standard 6-rib pulley system out of the box. Steeda provides everything required for the conversion including all pulleys, a new balancer and 10-rib hub, billet idlers, and a special tensioner. 8 A comparison between a 10-rib and 6-rib blower belt there won t be any belt shredding or slipping with the new Steeda setup. A DiabloSport MAFia was used to increase the limit of the MAF sensor. Our car uses a custom JPC tune for the supercharger system, and MacDonald used DiabloSport software and a Trinity hand-held flash device to accomplish the task PRESENT HOT MUSTANG PROJECTS MMFS V.indd 60

4 knowing there were essentially two modifications is a gratifying experience. The car, however, is not that much fun in this trim. More fun meant more power enter a Ford Racing High-Output Supercharger system. This modification, unfortunately, isn t something you want to tackle trackside, so we waited for an opening at JPC Racing s shop. Once in the shop, the Stang was upgraded with a Ford Racing twin-screw supercharger, Ford Racing 47-lb/hr fuel injectors (GT500 injectors), Steeda 10-rib pulley system, and a Steeda heat exchanger. 10 It was strapped to the chassis dyno, where JPC s Kevin MacDonald calibrated the PCM for the new injectors and 11.5 psi of boost. It made 458 rwhp with the out-of-the-box six-rib system. The Steeda 10-rib drive system was installed and increased boost to 12.5 psi. The final result was 479 rwhp it was still mostly stock, down to the exhaust manifolds, OEM cats and mufflers, and even stock drivetrain including 3.31 gears and torque converter. Timing was set at 17 degrees for 93-octane fuel. A set of Mickey Thompson 275/40-12 We hit nearby Maryland International Raceway once the dyno wheels stopped moving at the JPC Racing headquarters. Best time was an at 117 mph with a foot time on the 26c A smaller TCI Street Fighter (at right, 3,500-rpm stall speed) torque converter replaced the larger stock converter. The TCI unit measures 10 inches in diameter verse the stock one that is 12 inches. A looser torque converter helps get the engine to its peak torque range on launch for quicker acceleration. 14 A larger Steeda heat exchanger was used to help cool the fluid for the liquid-to-air intercooler. 11 A second transmission cooler was added to help cool down the Redline transmission fluid. 15 A Moroso overflow tank (PN 41221) is used to assist the internal overflow reservoir that is located in the bellhousing. Our car spent just one day on the chassis dyno for a few tests and tuning. No dyno queen here. WINTER MMFS V.indd 61

5 16 The Axle Exchange one-piece aluminum driveshaft is not only stronger than the stock steel one, it is also significantly lighter. It saved 19 pounds of rotating weight and eliminated the weak factory CV joint Our initial supercharged testing was on a set of 275/40-17 drag radials, while our driveline upgrades were accomplished on a set of Mickey Thompson ET Streets (26x ). We used the stock 17-inch Bullitt wheels in both instances. 17 drag radials helped traction, and an at 117 mph was the result. The 07 was fun on the track, but the real joy was tooling around on the streets. With only light pedal application, the car behaves like stock and even knocked down 24 mpg on road trips. Heavy throttle action makes the Goodyear 18-inch street tires beg for mercy. The up-shifts at WOT helps us make road art in the form of long strips of rubber. But while mid-11s is impressive, we knew more potential lurked. The car makes 479 rwhp through the automatic and that is a lot, says Burcham. We could add headers or more boost, but the stock Three- Valve is nearing its limits. I ve seen some auto cars live above 500 rwhp and others fail at 450 rwhp. Armed with that data, our attention was refocused on accelerating quicker, not adding more power. To do this, a set of Ford Racing 4.10 gears, an Axle Exchange one-piece aluminum driveshaft, and a TCI 3,500-rpm stall speed torque converter were installed. MacDonald adjusted the transmission tuning to compensate, and your author flew down the track in just seconds at 120 mph. Using a DiabloSport Trinity, I added one more degree of timing (18 degrees), and the result was an even quicker at 120 mph. These modifications won t show up on a chassis dyno test you can only realize them at the track. We ve take the GT from 13s down to low 11s with relative ease, a pleasure since this car isn t a dyno queen. HMP Sources Another driveline upgrade was the addition of 4.10:1 rear gears from Ford Racing. The steeper cogs helped the car accelerate quicker, but it still stays below the rev-limiter through the traps at 121 mph. Axle Exchange 973/ DiabloSport 877/ Ford Racing 800/FORD-788 JPC Racing 866/JPC-RACE Mickey Thompson Tires and Wheels 330/ Moroso 203/ TCI 888/ Steeda Autosports 954/ PRESENT HOT MUSTANG PROJECTS MMFS V.indd 62