The coils were easy, and the pulley swap for the Three-Valve bullet in our test Mustang continued that theme. It involves changing just two pulleys--on the crankshaft and water pump--as opposed to swapping three pulleys, as we do on pushrod engines and Two-Valve modulars (the alternator pulley is replaced on these two engines), and the task can be done in about an hour. The Granatelli Motor Sports pulleys we installed reduce crank and water-pump rotating speeds by 25 percent, which helps increase a trey-valve's rpm rate, and thus enables the engine to generate more power due to reduced drag on its crankshaft and water pump.
Granatelli Motor Sports' S197-Mustang cold-air-induction system was the fourth piece installed on Abraham's '06 'Stang. The kit is highlighted by its smooth-flowing cast-aluminum tube and bolts directly in place of the factory's airbox. The benefit in installing a cold-air kit for '05-up 'Stangs is twofold. First, it replaces the restrictive factory airbox and paper filter with a high-flowing performance filter. Second, by eliminating the really aggressive bend that's found in stock inlet tubes, the air has a cleaner/less turbulent direct flow to the throttle body.
 There's no cutting involved...  There's no cutting involved with an S197 muffler swap. Corsa's stainless-steel Ultimate Touring System is completely slip-fit, bolts in place of the stock cans, and includes new crush-style clamps that help to make the job a hassle-free proposition. (We recommend loosening the OEM H-pipe before installing the new mufflers. Doing this makes aligning the system a lot easier and ensures the mufflers look uniform when they're finally tightened down.) |  Each stainless muffler is...  Each stainless muffler is finished with a clean, polished 4-inch tip that looks good at the end of a new Mustang. |  This is an inside glimpse...  This is an inside glimpse of a Granatelli Motor Sports Pro Series Xtreme coil. Each coil pumps out roughly 65,000 volts with literally no resistance (0 ohms), and features an isolator ring in the middle of its winding to eliminate RFI/EMI interference. |
The air-inlet tube for the cold-air/nitrous package comes from GMS with a Zex nitrous fogger nozzle already installed. However, the nozzle was removed for this stage of the project, which allowed us to gauge the CAI's impact on Abraham's 'Stang without any hint of the nitrous system. Although the GMS S197 cold-air system isn't supplied with a tune, we found that the influx of cooler high-pressure air affected the engine's air/fuel mixture to the point where it was definitely necessary to add fuel (14.7 at WOT).
Using the DiabloSport Predator, Ricardo selected the device's pre-programmed calibration for a comparable cold-air system, which is set up for a 90mm mass air, and we were instantly rewarded with safe (actually, rich) air/fuel of 11.8, 30 degrees of timing at WOT, and a final horsepower gain (from adding only the CAI) that was impressive, as you can tell from the dyno chart.
In the last four years, nitrous oxide use seems to have turned into a lost art of sorts when it comes to hopping up street/strip S197 Mustangs. That's not to say there aren't any nitrous kits that are compatible with the fuel-injected Three-Valve engines, because there are plenty. However, more and more enthusiasts are turning to supercharger and turbocharger systems to carry their Ponies to the big-power zone. Trust us--it doesn't have to be that way, especially when you're modifying your Mustang on a strict budget.
While the majority of our upgrades for Abraham's '06 GT affect naturally aspirated performance, we also added nitrous with a really cool, bolt-on system developed by Granatelli in conjunction with Zex. The GMS/Zex cold-air/nitrous system for '05-'09 Ponies is the most elaborate component in our upgrade package, and as such, took the most time to install. The kit is highlighted by the cold-air tube we detail earlier in this report, which is predrilled and tapped to receive a single fogger-style Zex nitrous nozzle. Also included with the nitrous package is a Granatelli Motor Sports' dual-window rpm switch, which we programmed to activate the nitrous shot between 3,000 and 6,000 rpm and only when the throttle is wide open.
We found that installation of the GMS/Zex S197 nitrous system is best handled by two people, as there are many tasks that must be performed to ensure it's done properly. GTR's Ricardo and Chris had the juice on and flowing in about four hours, and we headed back to the dyno to see what this final enhancement does for our test ride's power output. The photos and dyno details await you, so keep reading to see how our Three-Valve stocker fared when we started adding parts--and shooting juice.
 We called on DiabloSports's...  We called on DiabloSports's Predator hand-held flash tuner to help fine-tune the test 'Stang's engine after the Granatelli Motor Sports cold-air system was installed as the larger tube and smoother airflow it promotes caused air/fuel to lean out at wide-open throttle. Subsequently, Ricardo also used the Predator to make timing changes during the dyno runs using nitrous, retarding a total of 6 degrees from 5,000 rpm to 6,000 rpm for our 100hp shot (89-octane pump gas and spark plugs gapped at 0.045). |  |  Changing coil packs is as...  Changing coil packs is as easy as swapping spark plugs. Ricardo and Chris each took a side and had the coils swapped in 15 minutes. Note that we didn't change spark plugs (to a colder heat range) or regap the factory plugs even though we're adding nitrous oxide. The coils will compensate for the factory plug gap, and we'll also make fuel and timing changes with the DiabloSport Predator if we find it is necessary as we continue to add parts. |
 Note the size differences...  Note the size differences between the new underdrive pulleys (both on the left) and the GT's factory pulleys. Despite the dramatic changes in the pulleys' diameters, the OEM serpentine belt is reused after the swap is complete. |  The bolt in Ricardo's left...  The bolt in Ricardo's left hand is included with the pulley kit and replaces a factory stud for the alternator bracket (in Ricardo's right hand), which is too long and will not clear the new water-pump pulley. |  After disconnecting the two...  After disconnecting the two fluid reservoirs (coolant and power steering) from the radiator support, Ricardo removes the fan assembly to access the crank and water-pump pulleys. Removing the pulleys is straightforward, however, a claw-style puller is required for extracting the crank damper. Also, the Granatelli Motor Sports-supplied longer center bolt must be used for removing and installing the old and new crank pulleys. |
 Here's a look at the Three-Valve...  Here's a look at the Three-Valve bullet with its new SFI-approved crank pulley and water-pump pulley from Granatelli Motor Sports. Both pulleys are final-installed using the factory bolts. (Again, the supplied longer center bolt is required for putting on the crank pulley). Put a small dab of silicone and a coating of red Loctite on the crankshaft bolt to keep oil from leaking past the bolt, and prevent the bolt from walking out after it has been torqued. |  We chose to remove the Zex...  We chose to remove the Zex nitrous nozzle from the Granatelli Motor Sports air-inlet tube in order to test the tube completely on its own. A 1/8-inch fine-thread (#27) NPT plug was used to close off the nitrous port. |  A threaded port for the included...  A threaded port for the included crankcase ventilation system (fitting and tube) is positioned on the bottom side of the aluminum air-inlet tube. Ricardo recommends using Teflon tape on the fitting to ward off a potential vacuum leak in this area. |