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Superformance Slab Side Cobra - The Starting Line Featured Vehicle

Updated: May 28

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This recently assembled narrow body "Slab Side" Cobra replica by Superformance is currently the crown jewel of The Starting Line's inventory. On the surface, this car is an identical copy of model CSX2588, the last 289 Cobra that Carroll Shelby sold to the public in 1965. Underneath the body, however, there are a few modernizations added for the sake of practicality.



What is a slab side, anyway? Well, when Shelby began designing the Cobra around 1961, he was borrowing shells from a British sports roadster called the AC Ace. Right away, the engine bay was modified to replace the Ace's two-liter straight six with a 260 cubic inch Ford small block V8, then a 289 V8. This initial build of the car would be dubbed the slab side by enthusiasts and replicators due to the flat, plain appearance of the body compared to later examples. The Cobra design evolved over the next few years, with Shelby hoping to turn the little roadster into a world-beating race car.


427 Cobra continuation    Image by Superformance
427 Cobra continuation Image by Superformance

He would accomplish such a feat by re-engineering pretty much the whole chassis, widening it to accommodate a powerful 427 big block and fat racing tires. This new Cobra was blisteringly fast around corners, but had an aerodynamic disadvantage on the long straights of Le Mans. Shelby would alleviate that issue by creating the 200 mile per hour Daytona, a direct competitor to Ferrari's 250 GTO. The Daytona was essentially a Cobra with a much longer custom coupe body to efficiently cut through that French air. The longer wheelbase pushed the engine toward a mid-front engine layout, greatly improving weight distribution. It was also the rarest of the rare, with only six original cars built.


The Daytona coupe was a radical departure from previous Cobras.    Image by Superformance
The Daytona coupe was a radical departure from previous Cobras. Image by Superformance

As you can probably tell, there are many possible inspirations for a replica Cobra, but we just love the laid back vibes of the slab side compared to the manic performance of the racing versions. The narrow body car may not be quite as much of an eye-grabber as the iconic 427 Cobra, but it certainly feels right at home along gently curving roads, or at VIR's parade laps.

There are countless replica kit providers out there, with wildly varying levels of quality, but Superformance has been delivering top-notch, authentic cars for 25 years now. In fact, they're the only kit manufacturer to bear the actual Shelby branding. They also officially-licensed replicas of the Daytona coupe, Ford GT40 and Corvette Grand Sport available for order. Several versions of their Cobra and GT40 even served as stunt cars for the recent blockbuster film, Ford vs. Ferrari.


Christian Bale as racer Ken Miles in an early 289 Cobra race car replica.    Image by Fox
Christian Bale as racer Ken Miles in an early 289 Cobra race car replica. Image by Fox

When it came down to reverse engineering this classic Cobra, Superformance used the original AC Ace design documents as the baseline. They recreated its welded tube frame chassis, while adding in some new structural reinforcements for improved safety and handling. The frame is furnished with fiberglass body panels. Much more economical than the original hand-beaten aluminum. It rides on Corvette-style transverse leafspring suspension and a steering box converted to rack and pinion.

Under the hood, our carbureted small block has been punched out to 347 cubic inches, giving it more than enough power for its 2,300-pound frame. That power goes out to a fairly modern Tremec TKO five-speed transmission, which should provide quicker acceleration than the tall geared four-speed in the classic car.



The Starting Line's sister company, RSC, is currently using the Cobra as one of the development benchmarks for our Chimera sports car prototype. The ultimate goal for this project will be to have a car equally poised for white-knuckle speed on the track, and moderate driving on the road. This Cobra satisfies the gentler end of that spectrum, while our open wheel development car aims toward the more furious end.



With that in mind, the slab side is not currently for sale. We're going to be holding onto this car for a while, but feel free to come down to an open house event and see it in person. We'll be at the Virginia International Raceway track day on May 22nd.

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