Eric English
March 8, 2015

Shelby Mustangs are a special breed. From the first generation to the new 2016 GT350, pairing Shelby with Ford’s ponycar transforms a mass-produced car into an auto enthusiasts’ sensation. Along the way, there have been many winners: rev-happy small-blocks, SCCA championships, aesthetic home runs, big-block brutes, and the most powerful engine ever fitted to a production Mustang—the 662hp 5.8L in 2013–2014 GT500s. But it all started right here—in a car built more than 50 years ago.

This photo from 2003 shows how the first Shelby Mustang (known as the “Street Prototype” or SFM5S003) appeared prior to its recent restoration. Looking very much the competition part, it provided huge fun for several different drivers over the years.

Recognized by Shelby cognoscenti as car SFM5S003, this Mustang’s official serial number breaks down as SFM (Shelby Ford Mustang), 5 (1965), S (Street version), and 003 as the consecutive production number. Also known as the “Street Prototype,” this Shelby is arguably as special as one gets. It would be easy to figure this one as the third GT350 built, but there’s an interesting story behind the numbers.

Documentation from the early months of the Street Prototype’s development identifies this car as “SFM5001”—denoted by a hand-scrawled marking above the firewall. Six months later when prototype work was complete and it was released for sale to the public, a permanent and official Shelby identification tag was affixed that carried the “003” number. Why the change?

Initial progress on the Shelby Mustang program was accomplished by Ken Miles, Bob Bondurant, Phil Remington, and Ford’s chief suspension engineer, Klaus Arning. Two Mustang coupes were sent to Shelby’s Venice, California, shop for chassis research and development in the summer of 1964 and were soon followed by a pair of fastbacks, which Pete Brock (see Take 5, HRM, Mar. 2014) used for development of aerodynamics and cosmetics. By late summer, Chuck Cantwell was hired as project engineer for what was then known as the “Cobra Mustang” program—essentially the lead for the entire project. Cantwell and his crew continued the development and were soon working out final specs, selecting parts, and identifying suppliers for what became the GT350 Mustang. Naturally, many of the parts suppliers were fellow California-based hot rod companies: Cyclone, Cragar, Ray Brown, Traction Masters, and others. For this reason alone, could there have been any better place to put together the first factory-built hot rod Mustangs?

Under the hood, hollow-letter Cobra valve covers, Tri-Y headers, Cobra-lettered high-rise intake, Holley 715-cfm carb, and HiPo 289 air cleaner are all early Shelby. A few oddities can be seen here by a sharp observer: 1) Only the earliest of GT350s used a tall 427-sourced air filter such as this one, as it’s believed the height caused the lid wingnut to tear the screen covering the fresh-air hole in the hood; and 2) the Street Prototype is missing the typical GT350 one-piece “export brace” that ties the firewall to the shock towers, as original pictures show it with the stock two-piece bracing.

Today the fate of the two early coupes and fastbacks are unknown, but three other fastbacks destined to be the first production units arrived at Shelby American in early November 1964. Two would be built as competition models (R-models), with the other being the Street Prototype seen here. This car was the first to be finished and was immediately pressed into service for company advertising and promotion by the end of 1964.

To provide photographic flexibility for promotional photos, car 003 was equipped for a time with the standard Kelsey Hayes 15x5.5-inch painted steel rims on the driver side and prototype 15x6-inch Cragar five-spokes on the passenger side. Early magazine coverage of the new Shelby Mustang often used Shelby-supplied images, and much of this featured the Street Prototype as well. How is this known? Well, befitting a prototype, a number of features were unique to this very first car—and quite distinct in period images. Among them were: a paper-faced tachometer in the GT350-specific gauge pod, a unique center cap on the Cobra-sourced steering wheel, unusual spacing between “G.T.” and “350” on the hand-painted rocker callouts, small prototype GT350 decals at the leading edge of the front fenders, and the aforementioned Cragar wheels.

The Street Prototype served its development, modeling, and public-relations tasks through the spring of 1965, then its purposes were complete. In a company memo dated May 20, 1965, Cantwell outlined bringing the car to production specs, and affixing it with a Shelby ID tag bearing the 003 number so it could be sold. Bill Moir was the first private owner, purchasing 003 through Leslie Motors in Monterey, California. It was treated like so many performance cars of the 1960s—as a starting point for something “better.” It wasn’t long until a Traco-built 289, dual quads, 4.56 gears, and high-11-second e.t.’s became part of 003’s history. Years came and went, and so did a handful of other owners. The car was restored in the late 1970s, then modified to full competition specs and vintage road raced for the better part of two decades. In short, this was not a GT350 left in factory condition, nor treated as a museum piece.

Current owner Mark Hovander became involved with 003 in 1999 when his friend Dave Lennartz purchased it. Hovander convinced Lennartz that the car deserved an authentic restoration to Street Prototype configuration, and assisted Lennartz in the search for original and date specific parts and pieces.

The 16-inch wood-rimmed steering wheel found on very early 1965 GT350s was sourced from the 427 Cobra parts bin, but was soon replaced by a 15-inch version for better leg clearance. Promotional pictures of the Street Prototype reveal the 16-inch version with a prototype center cap that incorporated the hood emblem from a 289 Cobra. Ray Brown–manufactured, competition-style seatbelts were standard on all 1965 GT350s.

Restoring any car to a high standard is a challenge, but an added burden in this instance was the uncertainty of what parts were used during prototype development, the point in time that Lennartz and Hovander were targeting. What was known was the way a white HiPo 289 fastback would arrive at Shelby American from the San Jose assembly plant prior to conversion. Fortunately, Hovander had forged relationships with both Cantwell and Brock, and other former Shelby employees directly involved with work on the early prototype cars. As recollections were tapped and archival photos discovered, a picture began to come into focus. Along the way, Hovander had the opportunity to purchase 003 from Lennartz in 2008.

After buying 003, Hovander drove the Mustang in competition guise for two years, loving every minute of it. He even expressed misgivings about returning the car to prototype status due to the fun he was having, but in the end he felt the car demanded restoration. In 2010 Hovander disassembled the Street Prototype to a bare shell in his home garage in Seattle.

Not surprisingly, this cap had disappeared long ago and was no doubt a handbuilt piece. Car 003’s original owner, Bill Moir, recently recreated the black center cap for the restoration of 003, which mounts an original Cobra emblem.

A goal was set to have 003 restored in time for the Mustang 50th Anniversary in 2014—an ambitious schedule as everything original to it had been removed and/or replaced with racing components. Surprisingly, most of the original sheetmetal was still present, including the rear quarters, whose wheel openings had been radiused for tire clearance much like the competition models.

Hovander had Dave Mackey do all the metalwork, including restoring the rear quarters, repairing holes opened when functional brake scoops were installed, refitting support members for the louvered C-pillar vents, and myriad other tasks. With the body back in original form, Dale Knutson laid down the beautiful Wimbledon White topcoat, and also sprayed the interior, engine compartment, and bottom side with factory finishes.

Early ads show car 003 with and without the unique Shelby center gauge pod, depending on the date of picture. Those with the gauge pod show a paper-faced tachometer on close inspection—adjacent to a non-production oil-pressure gauge.

As Mustang’s 50th festivities loomed, Hovander realized his reassembly was falling behind schedule. Help came from John Brown’s Thoroughbred Restorations in Piedmont, Oklahoma, who added the Guardsman Blue stripes and hand-painted GT350 lettering and side stripes, visible in early period photos. Brown also detailed the engine compartment and belly, then finished final assembly just in time for 003’s debut at the Amelia Island Concours in March 2014. There it would join SFM5R002, the first Competition 1965 GT350, to complete a duo that hadn’t been side by side since the Shelby American days.

As expected, the trunk is highly detailed, but what’s with the Weber intake? Original owner Moir told Hovander that shortly after purchasing the car in 1965, he set out to track down the source of an annoying clunk, which came from the rear of the car. Moir pulled up the fiberglass rear shelf, which deleted the Mustang rear seat, and found this very Weber unit underneath. How and why it got there is a mystery, but it assuredly happened during assembly at Shelby American. Moir held onto the manifold all these years as a memento, then let it go as one of several contributions he made to the restoration. As an aside, trunk-mounted batteries were installed on roughly the first 325 of the 522 1965 street cars.

All parts that went into the Street Prototype are date-coded originals, with the most difficult finds being prototype versions of the Shelby Cragars, Goodyear Power Cushion tires, a first production run example of the 715-cfm Holley, and date-coded glass. It’s such an authentic effort, the result of which is as 003 appeared in those magazine pictures and advertisements from early 1965. Never a museum car, it’s clear the Street Prototype has arrived at that status now. We asked Hovander how that sits with him. “I had to do it, but I’ve got another set of wheels with modern tires, and I put some miles on it now and then. Shelby, Cantwell, Brock, and the others never meant for these things to just sit around.” Indeed, they didn’t.

Anatomy of a 1965 GT350

The 1965 GT350 street car was far more than a fancy Mustang, it was a serious piece of Southern California hot rod engineering. All 1965s began as Wimbledon White Mustang fastbacks, equipped with the K-code solid-lifter HiPo 289, four-speed transmissions, 9-inch rearend, and front disc brakes. To that baseline, the following was added:


Cobra aluminum high-rise intake manifold

Cobra-lettered valve covers

Cobra-lettered, high-capacity aluminum oil pan

Holley 715-cfm vacuum secondary carburetor

Tri-Y tube headers made by Cyclone

Cyclone glasspack mufflers and side exhaust

Aluminum case BorgWarner T10 close-ratio four-speed

3.89:1 rear gears and Detroit Locker differential


Wood-rimmed steering wheel

Dash-mounted gauge pod with tachometer and oil-pressure gauge

Ray Brown competition-style seatbelts

Fiberglass rear package tray (deleted rear seat and mounted spare tire)


“Export brace” engine-compartment stiffener

“Monte Carlo bar” chassis stiffener

1-inch-diameter front sway bar

Quick-ratio pitman and idler arms

Relocated (lowered) upper control arms

Koni shocks

Ferodo front brake pads

10x2.5-inch Fairlane station wagon rear drums with metallic linings

Traction Masters override traction bars

Trunk-mounted battery (first 325 units)

15-inch wheels with Goodyear Blue Dot tires


Fiberglass hood with scoop and hoodpins

GT350 rocker stripes

Deleted Mustang grille “corral”

All About the Numbers

As explained in the main text, the Street Prototype was identified in its earliest days at Shelby American as SFM5001, via hand-scrawled lettering on the firewall. The two earliest competition models received similar 002 and 003 markings in the same location. This, of course, was prior to decisions being made about how and where production cars were going to be serialized. The first three cars remained in this condition, the underhood numbers sometimes visible in magazine articles of the day, until the Street Prototype was prepared to be sold in May 1965. In a memo dated May 20, Chuck Cantwell identified several items the Street Prototype would need prior to sale, including specific wording that states the car would be fitted with an official tag bearing the 003 number. Cantwell is uncertain today why he articulated the Street Prototype would get this tag when it was earlier labeled 001, but it’s known that the two competition models received official tags at the same time, bearing the numbers 001 and 002.

Still in the prototype phase at Shelby American, this period photo at Los Angeles International Airport was staged with an autocross feel. Note the side of the car featuring the bare-bones steel wheels and driver John Timanus in driving suit and helmet. This was one of the best images Hovander found showing details of the small GT350 decal on the front fender—also notice the absence of a dash-mounted gauge pod at this point in the development process.

This story is well known and documented today, but it was the source of confusion in the early days of Shelby Mustang research. In fact, those in the know at one time believed 003 was an original competition model, perhaps because period magazines showed a comp model with 003 hand-lettered on the firewall.