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 Daniel Vaughan | Jan 2022