1964-'66

The P70 Program

Carroll Shelby contacts Alejandro de Tomaso

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Shelby - De Tomaso

The P70 Story

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P70 / Sport 5000

The Gallery

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The Specifications

P70 / Sport 5000

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"This joint venture between Carroll Shelby and Alejandro de Tomaso was destined for controversy, but it was one of the best and most unique experiences of my life at a special time in racing history."

-Peter Brock, P70 designer

1964

Carroll Shelby contacts Alejandro de Tomaso

Historical Model
1964-1966

The P70 / Sport 5000

Carroll Shelby contacts Alejandro de Tomaso

Forward by P70 designer, Peter Brock

Passion and dedication to a project mean nothing if unforeseen events prevent its ultimate appearance on the world stage. The Shelby - De Tomaso P70 sports racer was such an endeavor.

The unlikely pairing of Carroll Shelby and Alejandro de Tomaso, two of the strongest egos in international motorsport, conspired to build a car they felt could defeat the best in the world and then the project fell apart virtually on the eve of its completion. While working for Shelby in Modena, Italy on the P70 the summer of '64, I received a call from Carroll telling me he'd cancelled the project and a ticket for my return was waiting for me at the airport in Rome.

Instead of competing as planning with its major contemporary contenters like Lola, Surtees, Cooper, Brabham, McLaren and Chaparral, in the United States Road Racing Championshio (USRRC) and later in the Can-Am and Europe, the P70 never turned a wheel in anger. Upon the dissolution of their partnership, de Tomaso leveraged the P70 to great marketing effect for Ghia, showing it with great acclaim and anticipation of its European racing debut at the Turin Auto Show in '65. Then inexplicably it was disassembled and placed in a darkened back corner of the De Tomaso factory in Modena to sit in silence for some forty years.

Discover the Design

Modena 1964

P70 Designer, Peter Brock, with Fantuzzi

P70

The Design

Words by designer, Peter Brock -

The decision to design and build the Shelby - De Tomaso P70 sports racer in '64 wasn't some spur of the moment decision by Carroll. It was a combination of the years' preceding events and the almost sudden materialization of Dave MacDonald as one of America's greatest young driving talents. The design of what eventually became the P70's body originated as a car I designed for MacDonald to be fabricated on a Cooper Monaco chassis. The "Lang Cooper," as it was called, was Shelby's attempt to take advantage of MacDonald's talent while keeping him interested in staying with the Shelby American team.

When the partnership with Shelby and de Tomaso developed, I pulled out my original plans for MacDonald's Lang Cooper and refined the lines for what would become the Shelby - De Tomaso P70. The P70 (Prototype 7 liter) was a unique, Italian-built, star-crossed racer, the result of a contentious partnership between Shelby and de Tomaso that in hindsight had little chance of lasting as the two had diverging priorities from its inception. Shelby had already reset his sights on using his successful Cobra program as a stepping stone to acquire Ford's juggernaut, cost-no-object GT40 program while de Tomaso used the completed P70 as the catalyst for his new production ventures with Ghia and Ford.

My design philosophy for the P70, in addition to my traditional small aerodynamic frontal area and downforce devices, was for all the components of the car to be integrated seamlessly within the body. First would be the reduction in frontal area. Instead of a mandated height for the windscreen it would be integrated into the form of the body. The purpose would be to make the airflow over the front of the body continue uninterrupted to the rear where it could be used to act upon the adjustable rear wing. By using an adjustable wing the drag inducing front area of a fixed spoiler could be eliminated. The airfoil shape of a rear wing would be lass than 30% of the area of a spoiler on the long straights, increasing top speed, but the driver would also have the option to activate the wing so it's angle of attack would slightly increase downforce for high speed sweepers. The P70's body-integrated adjustable rear wing later appeared on Ferrari's famed F40...twenty years after being introduced on the P70.

The large extractor vent in the P70's nose pulls hot air from the back of the radiator while also serving as a surface "spoiler" to reduce lift on the nose of the car. The engine rear body work of the P70 can be tiled upwards for improved access to the engine or easily removed completely to allow the engine and transmission to be unbolted from the rear of the spine chassis whilst the enclosed rear wheel of the P70 best demonstrates the freedom of design allowed in the American rules for the USRRC and later Can-Am series. In Europe the wheels had to remain completely exposed; a mandated "safety feature" to reduce any potential advantage that might be gained by superior airflow along the body's sides.

A Clash of the Titans

1964

A Clash of the Titans

Carroll Shelby leaves for Ford GT40 Program
Historical Model
P70

The P70 Story

Carroll Shelby contacts Alejandro de Tomaso

“In 1964 the unlikely pairing of Carroll Shelby and Alejandro de Tomaso, two of the strongest egos in international motorsport, conspired to build a car they felt could defeat the best in the world, the P70.” - Peter Brock.

At the time, Carroll Shelby was seeking to find a suitable replacement for his 289 Ford powered 'King Cobras’ as the ’65 USRRC racing series was fast approaching and he was driven to find a superior solution to outperform the 7 liter Chevrolets being developed by Bruce McLaren’s team. He turned to racing friend, Alejandro de Tomaso, as he knew that de Tomaso was an innovator as he had proved with his racing and first road car, the Vallelunga, which featured De Tomaso’s signature advanced lightweight ‘spine’ chassis. The intent was to put their joint project into production and provide it for sale to private racing teams.

The basic understanding was that Shelby would provide the financing, Alejandro would engineer the car and Peter Brock would provide the design and the fabrication would be conducted by Fantuzzi. The collaboration began on the hopes that De Tomaso would provide the chassis and convert Shelby’s 289 Ford/Cobra engine to 7 liters. The conversion of the engine to 7 liters was a key part of their partnership in order to compete with the big block Chevrolet engines.

The Shelby-De Tomaso “Prototipi” was known as the 'P70,' or ‘70P,' due to its planned 7 liter engine. However, over the course of the project the combination of two strong personalities and ulterior motives led to the dissolving of the relationship just before the cars completion. Shelby withdrew from the project as he was being enticed to turn his focus to the Ford GT40 race program and was displeased with the fact that he still had not seen his promised 7 liter engine. This parting of ways left a “chip” on Alejandro’s shoulder who would then see the project through to completion with the assistance of coach-builder Ghia. The vehicle was displayed at the Turin Motor Show in 1965, renamed the 'Ghia-De Tomaso Sport 5000’.

Before commencing the racing program, Alejandro revised the design and produced a second car under the Sport 5000 name. The combination of its 726 kg dry weight and its powerful powertrain enabled it to be compete with the best of the period. In 1966, the car was raced by Roberto Bussinello in Round 8 of the World Sports-car Championship, but retired on the opening lap. The Sport 5000 was never raced again.

"The Shelby - De Tomaso P70 remains as the sole mechanical tribute to what could have been a successful partnership. With its innovative super light central spine chassis and integrally mounted, load-bearing Ford V8 engine the P70 had a power-to-weight ratio that would easily match or beat the best in the world." - Peter Brock

Alejandro, upset with Shelby leaving the P70 program, used his extreme impetus and took the chassis developed for the P70, strengthened the frame even further, and used it as the basis for his next production model – the De Tomaso Mangusta.

The Road & Track Magazine Feature

1965

Alejandro see's project through to completion

P70 / Sport 5000

Road & Track Magazine

March 1966, by Ron Wakefield

One of the most interesting of the new cars at the Turin show was the new Group 9 competition car, the Ghia-de Tomaso. The project leading up to this car began first as a joint effort between Carol Shelby and Alejandro de Tomaso. The original project wasn’t carried through, however, but the basic design later was used on the Lang Cooper, which first appear in Fall, 1964. Now, developed further, the basic body shape has appeared on the controversial de Tomaso chassis, which consists of a central “spine” and the engine itself.

Pete Brock is the designer of the body, and hence we were somewhat puzzled when the car appeared as the Ghia-de Tomaso. The fact is that Ghia will provide financial backing for de Tomaso’s racing effort with the cars (there will be 10 of them initially) which makes it logical to apply the Ghia name.

Brock, until January the director of special projects at Shelby American, has now severed his connections with that firm. He designed the body as part of the Shelby end of the project and took his plans and templates to builder Fantuzzi in Italy for the development of the prototype, which is show on these pages in various states of construction. Instead of the usual quarter-scale model, one was build to 1/5 scale in clay in the Shelby offices, and to metric measurements. It was from this model that Brock defined templates and translated them onto paper. He then took the paperwork to Italy for use by Fantuzzi.

With the official withdrawal of the Shelby organization from any sponsorship of the car, Peter has become the agent and director of public relations for the project in this country. Also, he has now set up his own business, Brock Racing Enterprises, through which his services as a designer will be available.

The central spine chassis of the car is similar to that of the de Tomaso Vallelunga. It is not the first time that a spine-type chassis has been used, but it is unusual in that the backbone extends from the front suspension to about the longitudinal mid-point of the car, whereupon it forks out into the rails to which the engine mounts are attached. A reinforcing bracket from a point at the top front of the engine supplements the basic attachment, and the rear suspension is then mounted to brackets in the area of the clutch housing, with the longitudinal locating links running forward to brackets on the central spine. Thus the engine becomes a vital part of the chassis.

Where the Vallelunga have used 4-cyl Ford Cortina engines, this car has a special version of the Ford 289. De Tomaso has designed his own heads, rods, pistons and manifolds. The pistons, as we mentioned last month, contain the combustion champers; something on the order of the Audi engine. On the bench the engine has reportedly developed 475 bhp at 7300 rpm, indeed a very healthy figure for a 4.7-liter pushrod engine. Other engines could be used, of course, and the customer may be able to specify his choice.

The body shape is mostly convention from the engine froward and quite unusual from that point back. The tail section reflects some fresh thinking along aerodynamic lines, as have many of the new designs in the past two years or so. This business of the aerodynamics of racing cars will be getting a lot of attention for some time to come, for the ever-increasing speeds of these sports/racing cars have borough on problems of lift and stability that require solutions not yet known. Ask any aerodynamicist and he will tell you that ground-travel aerodynamics above 150 mph have been, at least until now, a no-man’s-;land. But now the subject is getting its share of attention and we’ll no doubt see some fascination shapes in the coming year.

Unusual also is the skirting of the rear wheels with sheet metal. It has been almost a universal practice to leave the rear wheels open, probably for easy access and the hope of better brake cooling but enclosing them as Brock has done promises. To improve boundary layer control in that area and should thus reduce drag a little. As can be seen from the photographs, access to the rear wheels is gained by tilting the engine cover back.

Initial plans call for assembly of 10 cars. De Tomaso will mange the racing effort (Group 9), running two cars per race entered. Masten Gregory will be one of the drivers, with another (probably Italian) yet to be chosen. The design is also amendable to the GT class, and to this end Brock has provided full-size doors. In the event it is used for that sort of thing, 50 will have to be build, of course, to quality under the revised FIA regulations now in force. Price, with engine, is about $13,000.

-Road & Track, March 1966

Mugello 1966

Sport 5000 racing a Ferrari 250 LM

Period

P70 / Sport 5000

Gallery

P70 / Sport 5000 in Period

Present

P70 / Sport 5000

Gallery

P70 at Present Day

Present

P70 / Sport 5000

Gallery

Sport 5000 at Present Day

P70 & Sport 5000

The Specifications

P70 / Sport - 5000

Overview

Quick Facts

•Collaboration between Carroll Shelby and Alejandro de Tomaso

•Designed by the famous, Peter Brock

Special Features: “Ring airfoil,” controlled by driver (gearshift actuated) for variable aerodynamics.

•Shelby left P70 program on eve of its completion to join Ford GT40 program

•Alejandro completed project with help of Ghia (a company he would later own)

•Final car became known as Ghia – De Tomaso Sport 5000

•Original MSRP: $13,000

•P70 chassis became foundation for the Mangusta.

Engine
  • Type: Ford – De Tomaso V8 (4,730 cc)
  • Layout: Mid-engined, longitudinally mounted.
  • Aspiration: Naturally Aspirated
  • Power Output: 475bhp @ 7,300 rpm
  • Power Ratio: 100.42 bhp / litre
Dimensions
  • Weight: 1450 lbs
  • Length / Width / Height: 4,084 mm (160.8 in) / 1,550 mm (61 in) / na
  • Wheelbase / Track: 93 in / 53.5 in fr / 54.5 in r
  • Fuel capacity: 30 Gallon
  • Wheels: (fr/r) 6 x 13 / 6.5 x 13
  • Tyres: Goodyear “Indy” (fr/r) 7.4-15 / 12.4-15
Drivetrain
  • Body: Aluminum over-steel tubing.
  • Chassis: Central spine chassis with engine sharing loads
  • Front suspension: Unequal-Length arms, coil springs, tube shocks
  • Rear suspension: Unequal-Length arms, coil springs, tube shocks, longitudinal arms
  • Steering: Rack-and-pinion
  • Gearbox: De Tomaso gearbox with Ford clutch
  • Brakes: Disc (fr/r)
  • Drive: Rear-wheel drive
  • Special Features: “Ring airfoil,” controlled by driver for variable aerodynamics.
Performance
  • Power to weight: 0.72 bhp / kg