On The Dyno
When we strapped Candy Barrientos' '06 Mustang GT to the Dynojet chassis dyno at GTR High Performance, its baseline power-and-torque output left us hopeful that the Granatelli Motor Sports bolt-on collection would bring the Pony's performance more in line with its cool color.
We started the install/dyno-test sequences with GMS Hot Street coil packs and then installed air-induction pieces (throttle body/CAI), and completed the evaluation of basic Three-Valve 4.6-liter bolt-ons with Granatelli's 3-inch off-road exhaust set.
As you see in the dyno chart and graph, each part installed produced gains in rear-wheel power and torque. However, it's important to note that Granatelli recommends installing its throttle body and cold-air-induction tubing as a combination, not separately. Purely for the sake of experimentation, we tested the throttle body individually (with the factory airbox and no tuning), and still recorded a modest gain. However, the ‘body and CAI really are most-effective as a combined unit, which does require tuning. For support in this area, we sought assistance from Bob Kurgan of Kurgan Motorsports in Braselton, Georgia.
Using DiabloSport's Chipmaster Revolution tuning software and working via the Internet (the InTune i-1000 on our side is the device that ports calibrations into the Mustang's PCM via the OBD-II port), Bob developed a tune for the CAI and throttle body, modifying fuel (initially adding, then trimming back) until a safe WOT air/fuel ratio (12.9: to 13.0:1) was achieved.
Our final addition of a 3-inch exhaust system brought a great rumble from the Three-Valve, but it also altered the engine's air/fuel by making the mixture just a bit lean. Bob nosed fuel up once again to compensate, and also pulled a degree of timing to ensure there will be no detonation for Candy to worry about when she throws down on the throttle and puts the new bolt-ons to work.