Thanks to Tom Thompson of...
Thanks to Tom Thompson of AMP Performance and Bernie Longjohn at Speedworld Dragstrip in Wittman, Arizona, we were able to immediately go from the dyno to the quarter-mile to see how Aaron Aldridge's '10 Shelby GT500 responds to a good shot of nitrous.
While the Mustang hobby has many, many facets, there are two sides that enthusiasts seem to be drawn to more than any of the others. The "show" side of our deal places emphasis on appearance. 'Stang owners hell-bent on having the baddest-looking Ponies on the planet. They often go to great lengths making the latest cosmetic changes-hot paint colors, trick graphics, slammed suspensions, and ultra-blingin' wheels. The other major component of hard-core 'Stangbangin', of course, is putting more go in the '86-'11 EFI cars that so many of us own and dig. As far as your power-mad, 5.0 Mustang & Super Fords tech editor is concerned, the more steam a 'Stang makes, the better!
As many of you are well aware, Shelby GT500s arrived on the Mustang scene in 2007 with a huge horsepower advantage over their S197 brethren. That advantage was no accident, either. The steam came courtesy of an Eaton-supercharged, 5.4-liter engine that set 500 horses off and running. Yes, Shelbys arrived and quickly became the answer to power-mad Mustang enthusiasts' prayers. True to our passion for making 'Stangs better, we didn't waste any time trying to find ways to improve GT500 performance.
A big Superman fan, the engine...
A big Superman fan, the engine compartment in Aaron's GT500 is accessorized with body-color-matching (Grabber Blue) battery, radiator, and master-cylinder covers, and a fusebox lid that has received custom airbrush treatments by Mo Madrid of Bad Boy Designs in Peoria, Arizona. Prior to our nitrous experiment, the stock-blown 5.4 put down 518 hp at the feet, thanks to an AMP 2.7-inch blower pulley, Bassani after-cat exhaust, and Diablosport tuning.
In our research, we found that basic bolt-on parts such as blower pulleys, cold-air-induction, exhaust pieces, and PCM calibrations easily carried GT500 rear-wheel horsepower past the 500 mark (using premium pump fuel), which certainly is impressive, considering the relatively low cost of parts and labor to get it done. Taking power to the next level requires making a move to harder-core replacements such as the larger superchargers or turbos.
While we've gone through all of 'em and have seen first-hand that the blowers and turbos all are serious players in the big-steam arena. We also know that making a move to one of the next-level power adders carries a pretty stout price tag. So, with that in mind, we decided to investigate the effect that good-old nitrous oxide has on a GT500. In our opinion, "juice" is the original late-model-Mustang power adder, and without question, it's the least-expensive choice of the trio we refer to as "The Big Three."
The Zex High Output Nitrous...
The Zex High Output Nitrous System for '05-present Mustang GTs (PN 82242; $639.99) comes with everything shown. A mechanically capable enthusiast can easily install it in a driveway or garage. Note the small, square box among the components. This is the unit's electronic TPS switch, which activates the system at WOT. While the solenoids and jets are the braun in this setup, the ETPS definitely is the "brain" of the entire operation.
The nitrous-plus-boost concept isn't new at all, and it's the type of upgrade that can be made with a good set of hand tools being the only requirement. Over the years we've seen how the gas can be used as an extra 'adder, and also for primary or secondary intercooling with blower and turbocharger systems (nitrous oxide also is used to quicken the spool speed of race turbos).
Since we know how wild nitrous makes factory-blown, DOHC 4.6 engines in street-driven '03-'04 Cobras, we're confident adding spray to the Terminator's big brother will reap similar good results. Our mission with this exercise is to find out how good, by installing a Zex High Output Nitrous System (PN 82242; $639.99) on Aaron Aldridge's fresh '10 Shelby GT500. We selected the Zex unit for its simplicity and 100-250hp adjustability. That puts its range on par with the aforementioned boost upgrades that do wonders on stock and modified engines in '07-'10 Shelbys.
For the sake of time and efficiency,...
For the sake of time and efficiency, AMP's lead technician, Chris Ciolek (left) and Jesse Allen teamed on the installation and had our test Shelby ready for dyno testing in a few hours' time.
As you'll see in the accompanying photos, the bolt-on and dyno tasks were put in the more-than-capable hands of Chris Ciolek and Jesse Allen of AMP Performance in Phoenix, Arizona. As an added performance treat, our friends in the desert also arranged for us to shoot juice at the GT500, in quarter-mile blasts at Speedworld drag strip, in nearby Wittman.

We decided to place the Zex...

We decided to place the Zex nozzle directly in the middle of "the curve" in the cast-aluminum intake elbow. Nozzle position technically can be anywhere along the intake-air channel (6-18 inches from the throttle body is optimal), and, of course, must be directed toward the throttle body.

Nozzle installation requires...

Nozzle installation requires drilling an 11/32-inch hole and tapping it with an 1/8-inch NPT thread. Care should be taken during this task, to ensure the proper-sized opening is bored in the elbow and the nozzle fits snugly inside.

After securing the intake...

After securing the intake elbow, Chris replaces the throttle body and factory air-intake system, and installs a fuel-rail adapter that will feed gas to the fuel solenoid. Looking back, it probably would have been cool to expand on this overall effort by replacing those pieces with parts like Ford Racing Performance Parts 63.5mm Cobra Jet throttle body (PN M-9926-CJ; $649.95), VMP Tuning's high-flow inlet elbow (PN ELBOW; $299.99) and JLT's carbon-fiber Shelby GT500 intake tube (PN CFBCAI-GT500-10; $199.00), but we wanted to conduct our test on an "as-is" subject.

When the valves on all six...

When the valves on all six mother tanks are open, the nitrous-filling station at AMP throws down serious pressure (900 psi). Chris uses the full blast to verify that our Zex nitrous solenoid is leak free.

Zex supplies all of the AN...

Zex supplies all of the AN -4, nitrous and fuel hoses for the installation, as well as the appropriate fittings.

Mounting the nitrous-bottle...

Mounting the nitrous-bottle brackets normally requires drilling holes in the trunk and passing bolts through them to secure the brackets to the trunk's floor. Chris makes this process easier by positioning the bolts, then welding receiver nuts to the floor.