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1965 ISO Grifo

Two contrasting versions of the Iso Grifo were introduced in 1963 at the Turin Motor Show, and both the race and road-going versions would soon earn an enviable reputation courtesy of the attractive styling by Giorgetto Giugiaro at Bertone and powerful V-8 powertrains. The A3/L ('L' for Lusso, or luxury) served as the GT form, while the A3/C ('C' for Corsa, or competition) was intended for competition and developed by Giotto Bizzarrini. The elegant styling was complemented by reliable engineering, helping the Iso Grifo A3/C to win its class at Le Mans on two occasions, in 1964 and 1965. This was a tremendous accomplishment considering the very competitive period of motorsport history and the company's origins - dating back to the 1930s as a producer of electric heaters and chillers.

Company History

Engineer Renzo Rivolta acquired the Isothermos of Bolzaneto in the late 1930s and moved the operations to Bresso in 1942. When World War II came to a close, the company built motorbikes and scooters. In the early 1950s, the company built a vehicle that was essentially a motorbike with a body. It was small and economical, and it offered protection from the wind and the rain. This new microcar was dubbed the Isetta and launched in 1953 following a company name change to Iso Autoveicoli. The diminutive, 'egg-shaped vehicle was equipped with an engine already powering the Isomoto 200, albeit with a slight increase in displacement. The four-wheel vehicle had a cockpit for two passengers and a unique front door that operated (and appeared) similarly to a refrigerator door.

From motorbikes and micro-cars, Iso took the unlikely transition into the realm of Gran Turismo vehicle production, competing directly with the well-established, high-end GTs of the era. Rather than attempting this on their own, they called upon some of the greatest and most talented individuals of the era and selected the proven and powerful American mechanical components to give it life. Introduced in 1962, the Iso Rivola IR 300 wore a design by Bertone, penned by Giorgetto Giugiaro, a chassis developed by Eng. Giulio Alfieri, and a V8 engine from the Chevrolet Corvette. The '300' in the vehicle's name indicated its engine output of 300 horsepower.

Next came the Iso Grifo A3/L and A3/C based on the GT 300 chassis and equipped with engines that ranged from 5.4 to 7 liters. The Grifo would become the company's best-known model and remained in production from 1965 through 1974. Giotto Bizzarrini was hired as a track engineer for the A3/C version with the bodywork formed by Piero Drogo's Carrozzeria Sports Cars in Modena using 1,700 rivets. Twenty-two examples of the A3/C were built before Bizzarrini split from the company to make his own variation.

Giotto Bizzarrini

Bizzarrini had accomplished much during his career by the time he joined Iso, most famously known as the Ferrari engineer responsible for the design and racing success of the GTO. After leaving Ferrari, Bizzarrini worked first with ATS, and then in 1962 started his own company Società Autostar, whose name was changed to Bizzarrini in 1964. Following his work with the Bizzarrini 5300 GT, he worked for Lamborghini and Alfa Romeo. The engine designed by Bizzarrini for the Lamborghini 350GT in 1964 would be used, with variations on the basic design, in every V-12 Lamborghini until 2010.

Iso Grifo

Bizzarrini worked closely with Iso's chief technician, Pierluigi Raggi, in developing a very sophisticated platform-type chassis for the 2+2 Iso Rivolta GT. The two-seater Grifo was based on a shortened Rivolta chassis with the engine positioned farther back in the chassis for improved weight distribution. The rearward placement was taken to such extremes on the A3/C that it is considered a front-mid-engine-placement. The engine in the GL sits several inches more to the front for the comfort of the driver and passenger but is still well behind the front axle.

The independent suspension system was comprised of wishbones, coil springs, telescopic shocks, and an anti-roll bar in the front while the rear used a deDion tube, coil springs, hydraulic shocks, and longitudinal struts. Renzo had encountered reliability issues with his personal GT cars, so the Grifo received a proven Chevrolet Corvette engine and transmission. The 5.4-liter small-block 327 V8 engine had variable power outputs of 300 to 350 horsepower and was backed by a Borg-Warner 4-speed manual transmission. The engines were manufactured in the United States, shipped to Italy, and disassembled and rebuilt before installation into the cars. The limited-slip differential is a Salisbury, with inboard disc brakes sitting alongside, as well as front disc brakes. The road-going Grifo wore a steel body with an aluminum hood.

A Targa Top version was introduced in October 1966 at the Turin Motor Show. In total, fourteen examples of the Targa were Series I and four were Series II. The Series II was introduced in 1970 and wore sleeker styling and hide-away headlights, and beneath the bonnet was a big-block Chevrolet 427 V8. The Grifo 7 Litri had been in use since 1968, equipped with the L71 big-block, Tri-Power version of the 427 engine. To cope with the increased output and size of the engine, numerous modifications were necessitated throughout the vehicle. The chassis components and engine mounts were reinforced and strengthened, and a large hood scoop (known as the 'Penthouse' and 'pagoda' due to its size) was added to clear the engine. The company proudly advertised that its luxurious Gran Turismo was motivated down the road by a minimum of 435 horsepower at 5,800 RPM and that its top speed was 300 km/h (nearly 190 mph).

The Grifo IR-9 'Can Am' version used an even more powerful Chevrolet 454 7.4-liter engine.

A few Grifos were returned to the factory and rebuilt, issued a new chassis, and sold again by Iso. The chassis numbering goes to 412, however, there were only 402 unique Grifos actually made (not including the A3/C models). It is believed that 90 examples were the 7-litre version. Including the A3/C models, 330 examples were Series I and 83 were SEries II, bringing the total to 413 cars.

The Iso Grifo was praised for its Italian styling and American power and was considered the fastest production car one could buy in 1966.

by Dan Vaughan

Coupe
Chassis number: 009

Giotto Bizzarrini designed the A3/L - a street car, L as in lusso or luxury - for Renzo Rivolta as a second string to his Iso Rivolta GT bow. Giorgetto Giugiaro, then at Bertone, penned the body. Under the hood of this dramatic 'artwork' is a Chevrolet 327 cubic-inch V8 blueprinted by Iso to make 400 horsepower attached to a hefty 4-speed gearbox. In 1965 Bizzarrini and Rivolta split, Giotto focused on his race A3/C and Renzo on his street car.

This car has a special place as an early prototype (#009), with approximately 400 street cars built in total.

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