S197 Mustang Bolt-Ons - The Power Of Three

Horse Sense: Power-mad enthusiasts should be careful when selecting various parts for improving their Mustang's appearance. The test ride in this story suffered a 10hp loss when the stock 17-inch wheels and tires were replaced with a 20-inch combination. A mere 3 inches in wheel diameter can bring on performance-killing weight. You probably don't think about that when you're buying the bling, but the dyno exposes it every time.

We can't help but get excited by the fervor with which Mustang enthusiasts have embraced modifying their brand-new Ponies, sometimes almost immediately after they've arrived at home from the car's maiden voyage from the dealership.

While the mods 'Stangbangers are currently making to their '05-'07 'Stangs can be classified as mild, wild, and everything in between, the one thing that seems to remain constant is the upgrades almost always involve installing an aftermarket part or system, stepping up the power output of the 4.6, Three-Valve engine sitting under the hood. This type of Mustang upgrading to make power isn't anything new. Improving a Mustang's rear-wheel horsepower and torque has always been the name of the game for dedicated enthusiasts. We're always experimenting with different methods of gaining more oomph for the powerplants motivating our favorite ponycars-especially these new ones.

For this exercise, we're taking a trip back to the future by installing and dyno-testing a collection of parts proven to be bonafide best-bang-for-the-buck methods of producing commendable, bolt-on power for post-'79 V-6 or V-8 Mustangs. Many diehard 'Stang junkies probably already know what we're getting at, but for readers who are not quite sure what parts we're talking about, they include: cold-air induction systems, post-catalytic exhaust (crossover tubes and mufflers), and underdrive pulleys.

This trifecta (and a gear swap) is probably the most tried-and-true group of proven Mustang upgrades ever discussed in any Mustang magazine. Countless tests show that increasing air volume/ velocity, reducing drag from serpentine belts, and setting up a freer-flowing exhaust system establishes a collective starting point for hopping up a 5.0 or 4.6, mainly because these upgrades are relatively inexpensive.

Thankfully, not much has changed for these three entry-level bolt-ons in the last 20-or-so years since they hit the 'Stang scene. They're still extremely popular, and despite this new age of calibrating PCMs with handheld flash tuners and custom chips, they're also not too complex when it comes to installing them.

In this report, we're covering our installation of S197 products from Gibson Performance Exhaust (after-axle mufflers), March Performance (underdrive crank pulley), and Steeda (CAI with high-flow inlet elbow and required SCT XCalibrator 2 flash tuner) on a new '06 'Stang GT. We'll also show how they measure up against the rollers of the Dynojet chassis dyno at GTR High Performance in Rancho Cucamonga, California. Our thanks go out to GTR's co-owners Gonzolo and Ricardo Topete, who came through for us and made this project a smooth effort. Gonzolo owns the 5,000-mile Mustang that's featured in this report. His brother Ricardo handled not only all the dyno testing, but also the parts installation, with help from GTR technician Dan Ellebracht.

In the following captions, check out the highlights of our day, as well as the all-important results of how our stock 4.6 responded to the new pieces.