Mustang MonthlyCar Reviews
2007 Shelby GT Modified By Shelby American Motorsports - Speed Shop Special
Can Shelby American Motorsports Turn An '07 Shelby GT Into A Modern Street Successor To The '65 GT350 R-Model?
In September 2009, I pulled into what is now known as Shelby American Motorsports, called the "Speed Shop" by Shelby employees. Back then it was called the Mod Shop, and technicians Damon Santiago, Tony Icovino, and Carl Seigfried reviewed the project with supervisor Phil Brown. The transmission and rear end were pulled, and the stock 3.55s were swapped for Ford Racing's 3.73 ring-and-pinion. The Centerforce flywheel, clutch, and pressure plate were installed, then the Tremec TR5050 six-speed and lightweight driveshaft. Next came the Watts link and the Shelby Pro-Plus brakes.
My first choice for wheels was a set of GT500KR mags, but I quickly learned that they were made from unobtainium, as one had to have proof of KR ownership to get a set. So I settled on Shelby's striking 20-inch Alcoa Forged Alloy wheels, as seen on the GT500 Super Snake.
The last items installed were the Kicker stereo and the cosmetic upgrades to the exterior, interior, and engine compartment. The Kicker subwoofer dramatically increased trunk space, saved 30 pounds, and sounded better than the Shaker. While most of the Shelby cosmetic items are easily added, as a chief judge at the Pebble Beach Concours for two-plus decades, I felt any changes should be done by Shelby, the original constructor. That way they are forever authentic.
At the time of the build, Shelby wanted to enhance the engine performance. We talked about a number of supercharging options, but the GT350 R was naturally aspirated. Also, while the idea of 100-plus blown horses was alluring, a supercharger adds weight right where you don't want it-on the nose.
I decided to stay true to the original R concept and modify the engine's internals. Shelby was not set up for that type of work back then, so AMP Performance in Phoenix did the build. Before securing parts, I conferred with Gary Patterson. I wanted the end product to be as "pure" Shelby as possible.
AMP's Chris Ciolek and Jesse Allen capably performed the engine modifications. Ford Racing's CNC ported heads and high-lift hot rod cams, along with a custom tune, provided the majority of the horsepower boost. Steeda underdrive pulleys and high-flow inlet elbow, and Bassani long-tube headers and crossover-pipe, completed the changes.
Both Gary Patterson and Shelby American's chief development driver Vince LaViolette tested the car. They gave it a big thumbs up. During one drive when Patterson had the speedometer buried, I asked how fast we were going. He casually replied, "Probably 155." And the car was still pulling strongly.
I was happy with the performance, but the appearance wasn't quite what I envisioned. I still desired the more restrained look of the KR wheels, feeling their 18-inch diameter and lower rolling resistance was more appropriate for a GT350 R successor. After months of inquiries in and outside of Ford and Shelby, unobtainium was finally obtained! The deal for a set of KR wheels was done, and my Alcoa wheels quickly found a new home on a friend's '10 GT500.
With KR wheels in place, it was time to head to Vegas for the final piece of the puzzle. Ford Racing's new three-valve performance intake manifold came out a few weeks after Shelby opened Shelby American Motorsports. I would have returned to AMP but the purist in me wanted Shelby to do the installation. By then, SAM was set up to do most anything on most any car, including dyno testing for rear-wheel horsepower.
The baseline dyno run showed 345 hp. Ford Racing's 62mm billet aluminum throttle body bumped power to 349. The manifold pushed it to 358, then Shelby's Gil Nevarez went to work with a custom tune to get it to 363, or right around 420 at the crank.