KJ Jones Senior Technical Editor
January 27, 2011
Photos By: Courtesy of Anderson Ford Motorsport

This is the second segment of our diary on the power improvement of Nikki Wilson's ragtop '02 'Stang. If you missed our first report ("Breathe In, Breathe Out," Jan. '11, p. 108), we're following this three-part upgrade effort to show '99-'04 Mustang GT owners some basic mid-level and higher-end engine upgrades that are doable in the driveway, and offer tremendous bang-for-the-buck performance.

In initial tests, Nikki's once-stock Pony was treated to both of Anderson Ford Motorsport's bolt-on horsepower packages. The 30hp package consists of BBK's 78mm throttle-body/plenum; an ASP crank damper and underdrive pulleys; and Bassani mid-length headers, off-road X-pipe, and after-cat exhaust system. To that, we also added AFM's N-22 camshafts, Power Pipe, and Abaco DBX 97B programmable mass-air meter.

In total, those additions are worth 60 horses at the feet, and brought our test Mustang's naturally aspirated grunt up to 291 hp (from its anemic 227.40 baseline) and 309.30 lb-ft of torque. Now, when you consider this kind of naturally aspirated horsepower in the grand scheme of things, anything even remotely close to 300 ponies is excellent for a Two-Valve 4.6, especially an engine with stock cylinder heads.

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However, as adding a Kenne Bell 2.6-liter Twin Screw supercharger ultimately is the final plan for Nikki's GT-and the subject for our third and final report that will appear in a future issue-we decided to swap the stock engine with a D.S.S. SuperMOD 5.0-liter short-block (PN FE 50SM BOOST), which was topped with Trick Flow's 4.6 heads (PN TFS-51900002-M44), intake manifold (PN TFS-51800003), and Anderson's N-52 camshafts (PN AFM N52).

Making the move to this hopped-up engine makes all good sense, mainly because despite the increase in cubic inches and naturally aspirated horsepower it brings, the new engine essentially is the same thing (structurally) as the bullet that is being removed from Nikki's 'Stang. The exhaust system, wiring, and all other necessary pieces fall right into place with this exchange, making for a clean (and stealth) transformation that will really make big steam when topped off with KB's blower.

As you'll see in the following photos, Nikki and her crew perform the entire transition process in the driveway and garage. The weekend project is something any ambitious and mechanically inclined 'Stangbanger can accomplish with the help of good friends and a six-pack or two.

On The Dyno Upon completion of the Two-Valve engine swap in Nikki Wilson's '02 Mustang GT convertible, the 'Stang was delivered to the ever-ready Dynojet chassis dyno at Anderson Ford Motorsport; the same dyno that was used for Part 1 of this 4.6 upgrade project. As expected, the new powerplant brings about a need for PCM calibration, and Dyno Danny Biggs is AFM's man behind the Abaco DBX and DiabloSport Chipmaster Revolution tuning software.

According to Rick Anderson, "Tuning Nikki's new engine was not hard. We started with DiabloSport's plug-and-play, 93-octane calibration, which Danny modified to achieve optimum air/fuel. This engine has 9.6:1 compression. I really think we could have made 10 more horsepower at the wheels with the 10:8-to-1 SuperMOD stroker (still with pump fuel), but since we plan to add a supercharger next, the lower-compression engine is the best way to go."

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You may recall us mentioning our interest in seeing how the 75mm throttle body works with this combination. Rick says the "small" 75mm piece actually hurt the setup by about 10 hp (remember, a 78mm 'body was used in the first project).

"If you can find an '01 Bullitt throttle cable (the part has been discontinued by Ford), going with a ported, oval-shaped 100mm throttle body is the better option for a naturally aspirated 5.0 modular with Trick Flow heads, intake, and hot cams," Rick says.