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1963 ISO Grifo A3/L

The legacy of Iso Autoveicoli S.p.A. stretches to before the onset of World War II, and over the years has been known as Isothermos, Iso Rivolta, and Iso Motors. Among their contributions to the local and global economy were electric heaters, chillers, motorbikes, scooters, and various types of motorcars including the microcar. The company was founded by a visionary and engineer named Renzo Rivolta who kept pace with the pulse of the market. In the years immediately following World War II, he recognized the potential for an affordable means of transportation in Italy and all of Europe. This prompted the production of scooters, motorcycles, small trucks, and the Isetta mini-car. BMW would later acquire the license for the Isetta microcar and its popularity led to the company's re-establishment of financial stability. Iso would eventually explore the Gran Touring (GT) car production by combining Italian styling with American power. The pinnacle of the Iso GT cars was the Grifo with styling by Giorgetto Giugiaro of Bertone and engineering by Giotto Bizzarrini, the lead engineer for developing the Ferrari 250 GTO.

The Iso Grifo

The Iso Grifo was produced between 1965 and 1975 with 330 examples of the Series I and 83 of the Series II. Of the 413 examples created, 90 were equipped with seven-liter engines, 23 examples of the Series II had a five-speed gearbox, and four Series II cars had a Targa top.

The Grifo joined the Iso Rivolta grand tourer which had been introduced in 1962 and would remain in production through 1970. It was a 2+2 coupe 'family car' that used a 5.4-liter Chevrolet 327 V8 engine, wore a design by Giugiaro, and benefitted from the engineering expertise of Bizzarrini and Pierluigi Raggi. This was the first luxury automobile introduced by the company and a total of 797 examples were built during its production lifespan. It used pressed steel and a welded panel chassis with a wheelbase size of 2700mm (106.3 inches) and a length of 4,760 mm (187.4 inches). Its suspension was a de Dion setup in the rear with unequal-length wishbones in the front. Disc brakes all round provided the stopping power.

The Grifo had sportier styling than the Rivolta and its wind-cheating design was built for both the road and the track. The Iso Grifo A3/L ('L' representing Lusso, Italian for 'luxury') was the road-going luxury version while the A3/C (C for Corsa) wore an alloy body, had its engine moved back about 40mm (1.6 inches), and intended for competition.

The Grifo rested atop a shortened version of the Rivolta GT chassis that measured 2499mm (98.4 inches) and a length of 4430mm (174.4 inches). Nuccio Bertone built the prototype example based on the rolling chassis and mechanical components supplied by Iso. The Grifo A3/L concept car was introduced in 1963 on the Bertone stand at the Turin Auto Show while the race-bred, unpainted Iso Grifo A3/C was on the Iso stand at the same show. The production version of the Iso Grifo A3/L received a few styling changes and its name was changed to the Iso Grifo GL. Both versions would become successful in their own right, including a class victory at the 24 Hours of Le Mans two years later by the A3/C.

Initially, both cars were equipped with Chevrolet Corvette 327 cubic-inch V8 engines backed by a Borg-Warner 4-speed manual transmission. The limited-slip differential was a Salisbury unit, and both used the same chassis. The engine location in the A3/C improved weight distribution and is considered a front-mid-engine placement. With the engine residing farther forward in the GL (albeit well behind the front axle), interior space was improved which catered to the luxury persona. The Grifo GL wore a steel body with an aluminum hood and the A3/C used aluminum components wherever possible. The single carburetor on the engine was replaced with four side-draft Weber carburetors, and along with tuning of the intake rams, improved output to around 400 HP. The potent engine, combined with its 2,750-pound weight (compared to 2,970 lbs of the A3/L), the A3/C was capable of 170 MPH.

Just like the engines installed in the RI 300, each unit was taken apart before they were installed in the cars. The 327 CID V8 had overhead valves, a single Carter 4-barrel carburetor, and developed approximately 340 horsepower at 6,000 RPM. In 1968, Piero Rivolta created a more powerful version of the Grifo by installing a Corvette 427 cubic-inch L71 big-block engine with Tri-Power creating a new model named the Grifo 7 Litri. The engine was much larger and more powerful than the 327 V8 requiring several design and mechanical modifications. The hood received a large scoop, dubbed 'Penthouse' due to its size, which accommodated the engine's deck height. In this guise, the engine offered 435 horsepower at 5,800 RPM and had a top speed of 186 mph.

The Grio Series II cars of 1970 received styling changes to the front including the addition of hide-away headlights. The IR-9 'CanAm' version used the newer Chevrolet 454 7.4-liter engines instead of the 427 engines. The Grifo IR-8 of 1972 was equipped with a small-block Ford Boss 351 engine with an even taller hood scoop.

Bizzarrini Strada

The Bizzarrini Strada (also known as the 5300 GT) was built from 1964 through 1968, with 133 examples created. It began as an Iso, but disagreements between Bizzarrini and Rivolta brought a separation of these two companies. Iso retained the rights to the Grifo name and Bizzarrini obtained the rights to build the A3/C, plus mechanical components to build a limited number of examples. Named the Bizzarrini 5300 GT, it was available in either Strada or Corsa trim. It used the welded unibody platform of the Iso Rivolta 300 and was equipped with the 5.4-liter Chevy V8 engine. Along with the two-door coupe configuration, three spyder versions were also built, including the prototype with a full convertible top and two production versions with removable T-Tops.

by Dan Vaughan

Berlinetta by Bertone
Chassis number: 420001

This unique one-off design by Bertone made its debut at the 1963 Torino Auto Show. It was so well taken that at the Turin Auto Show, Nuccio Bertone wanted it to be his firm's show stopper; he was not disappointed. The car remained on the show circuit throughout much of 1964 and even made its way to the New York Auto Show on display at the J.S. Inskip stand. This car represented the next generation of cars to be built by Bizzarrini in the mid-1960s.

John Ling of Milwaukee, Wisconsin, had a total restoration done to the car. The car was shown at Pebble Beach in 1989 and won its class and the Gwenn Graham Memorial Trophy 'Most Elegant Closed Coupe' - this was the first time the award was bestowed upon a post-WWII automobile.

In 1992, Fred Reeser of Hartland, Wisconsin, purchased the car. The car won 1st in its Class at the 1995 Pebble Beach Concours d'Elegance.

In the late 1990's it was in a private collection and was then acquired by the Blackhawk Collection in 2001.

Berlinetta by Bertone
Chassis number: 420001

Iso introduced its second model, the Grifo, in 1962. Giorgetto Giugiaro of Bertone designed the body and Giotto Bizzarrini, creator of the Ferrari GTO, designed the mechanical components. The Grifo was powered by a Chevrolet 5.3-liter V8 fitted on a shortened Iso Rivolta platform. The Grifo was sportier than the Rivolta and was available in two versions, the luxurious A3/L and the sportier A3/C. Renzo Rivolta approved production immediately after seeing the first prototype, which led to a run of 402 Grifos being built from 1964 to 1974.

This car is the prototype number 001, and is powered by a Corvette 327 cubic-inch, 340 horsepower V8 engine, which gave the car a top speed of 171 mph. It has numerous unique features that did not make it into the production cars, including the unique hood and the stainless-steel wraparound roof band. It was exhibited at numerous motor shows including the 1963 Turin Motor Show and the 1964 New York Auto Show.

In 1962, the Milan car manufacturer ISO introduced its second model, the Grifo. The first was the Rivolta. Giorgio Giugiaro of Bertone designed the body, and Giotto Bizzarrini, the creator of the Ferrari GTO, engineered it. The Grifo was powered by a Chevrolet 5.3 liter V8 and sat atop a shortened Rivolta platform. The engine was placed in the front and drove the rear transaxle. The Borg-Warner T4 4-speed manual gearbox lacked overdrive, leading to problems in future endurance racing. At speeds, the driver had to back off the accelerator pedal to help preserve the life of the engine. With over 400 horsepower from the GM small-block and weighing less than 2200 pounds, the vehicle was able to achieve 190 miles per hour.

The Grifo was sportier than its predecessor and was available in two versions, luxury, and sport. The luxurious Grifo was dubbed the A3/L, while the sportier version received the title A3/C. Iso produced the Grifo A3/L, while Bizzarrini developed the A3/C.

In 1964 it was entered in the 12 Hours of Sebring as well as the grueling and fiercely competitive 24 Hours of Le Man's race. During its racing career, it would capture a fourth overall and first-in-class victory at Le Mans.

During the production lifespan of the Grifo, around 22 versions of the A3/C were constructed. Due to disagreements, Bizzarrini and Rivolta parted ways in 1965. A deal was struck where Bizzarrini could still produce the Grifo A3/C cars but was unable to use the name. The new name was the Bizzarrini 5300 GT and American GT.

In 1968, a 6998 cc V8 engine became available and was later modified to 7443 cc.

by Dan Vaughan

Founder and head of Iso S.p.A. of Bresso, Renzo Rivolta, began his business 'Isothermos' in refrigerators before moving on to automotive design. The company is well known for its bubble cars and motorcycles, but its claim to fame lies in its performance GT car Iso Grifo. In 1960 Renzo was immensely attracted to the British Gordon GT prototype. Borrowing it for inspection, Renzo also borrowed some of its ideas for a new high-performance 2+2 sportscar. Already quite famous for producing the stunning Rivolta IR300, Iso Rivolta took it a step further and introduced the glorious Grifo in 1963.

Giotto Bizzarrini, the famous freelance Italian engineer, had worked for Ferrari but left to set up 'Prototipi Bizzarrini' in Livorno, Tuscany. It was here that Giotto designed and consulted for big names like Lamborghini, ATS, and Iso Rivolta. Young Giorgetto Giugiaro at Bertone designed the body while Bizzarrini focused on the mechanical side of the sportscar. What developed was the stunning Grifo A3L (L for Lusso/Luxury) prototype coupe. Debuting in Turin in 1963, the vehicle wouldn't be production-ready for another two years. The A3L curvy fastback featured a steel body with large engine-cooling grids in the front fenders, a Kamm-style tail, and a twin-mouth grille. Sharing a great distinction with the Chevrolet Corvette, the two-door coupe Grifo was well known for its sleek appearance.

The Grifo was also designed in a race version called the A3/C (Corsa) with a spectacular modified alloy body. Bizzarini had been the designer behind the Ferrari 250 GTO and he dubbed the A3/C his 'Improved GTO'. One of the first front-mid-engined cars ever built, the A3/C's engine was moved back about 16 inches. Both versions of the Grifo were built simultaneously and both models were debuted in the same year. Bertone debuted the Grifo A3/L prototype at the Turin Auto show, and Iso unveiled the under construction competition version; the Iso Grifo A3/C. The motoring press was incredibly impressed with both models.

Though design tweaks to the prototype were made, Iso set about getting the Grifo A3/L production-ready. In an attempt to make the Grifo 'less aggressive' a facelift was in order, and it transformed the model into an even more stunning model. The Grifo shared the Rivolta's running gear and suspension but was tuned for higher performance.

Considered by some to be the most elegant-looking Gran Turismo (GT) supercar ever created, the Grifo received the Chevrolet Corvette's 327 V8 (5.4 L) engine. Speedy and reliable, the engine was either 300 or 350 hp and was mated to a Borg-Warner 4-speed Toploader. The engine was ordered in the U.S. but would be taken apart precisely and blueprinted before being installed, in the same way as the Iso Rivolta GT. With a top speed of 171 mph, the supercar had over 400 hp and weighed less than 2,200 pounds. The front suspension was through conventional wishbones and coil springs, while at the rear was a coil-spring De Dion live axle located by radius arms and Watt linkage. The brakes were four-wheel discs.

Giotto spent all of his time and energy on the A3/C, while Renzo Rivolta focused on the A3/l. This, unfortunately, brought some tension between the two men. The Grifo GL was produced at Bresso while the A3/C was produced at Piero Drogo's Sports Car of Modena under the watchful eye of Giotto. The A3/C was raced at Le Mans (Edgar Berney/Pierre Noblet) in 1964. The prototype raced well until brake issues required a two-hour pit stop before the car finished in 14th place. A disagreement between Renzo and Bizzarrini ended the cooperation in 1965, and the production of the street Grifo GL and the competition Bizzarrini A3/C were separated. Only 22 examples of the Bizzarrini Grifo A3/C were constructed.

Giotto produced a line of Bizzarrini 5300 Stradas and Corsas from the improved A3/C. The 'Grifo' name was dropped from any connection to Bizzarrini at this time. Bizzarini went on to build both Bizzarrini Strada and Corsa and had the alloy bodies constructed by BBM of Modena.

Bizzarrini introduced the scaled-down 1900 'Europa' in 1967. Some models received Alfa Romeo engines, while some received a tuned-up version of the Opel 1900 engine. About seventeen models were produced which made it one of his rarest designs ever. The Barchetta version, the P538, was even rarer with only three models produced. Around 155 Bizzarrini Stradas and Corsas were built before Bizzarrini closed down in 1969 due to bankruptcy. The remaining parts and cars were sold off.

In production form, the Grifo developed 390 hp and could reach 68 mph in first gear. A singular Grifo A3/L Spyder was debuted at the Geneva auto show by Renzo. In 1965 production of Iso Grifo GL began. The first-ever Grifo with Targa Top was shown in Turin in October 1966 and would be one of 13 Series I Targas ever built. Four series II Targas were eventually produced.

The interior of the Grifo was incredibly comfortable and could rival many Italian supercars of the day. The Grifo handled beautifully and was a solid supercar that appealed to nearly everyone. Because of its low build of only 47 inches, the Grifo was extremely fast and had excellent aerodynamics. Unfortunately, the Iso marque wasn't as prominent as Maserati or Ferrari, and attracting orders from the affluent customers that they needed was difficult.

The Grifo 7 Litro was debuted in 1968, powered with a Chevrolet L71 big-block engine, a Tri-Power version of the 427 engine. Changes had to be made to the car for this seven-liter engine to fit, including the addition of a hood scoop. The 7 Litro had a claimed top speed of 186 mph and produced 435 hp at 5800 RPM. The Grifo Series II was introduced in 1970 and included styling updates in the nose section of the car that was sleeker and hid hide-away headlights. Four Targas were built in this new series. The engine for the IR-9 'Can Am' version was switched from the 427 engine to the newer 454 engine. Iso began to use a small-block Ford Boss 351 engine which could be easily recognized by their taller hood scoop. In 1972 production ceased, and Iso S.P.A. closed its doors in 1974 during the oil crisis.

During its production span, a total of 413 Iso Grifos were produced. 322 Series 1 models, 78 Series II cars, 90 of these being the 7 Liter. Twenty-three of the Series II 5-speeds and 4 of the Series II Targa models were produced. Today the Grifo is an incredible collectible due to its extremely rare production.

by Jessican Donaldson