Iso Grifo

In short

• Built at Bresso, Italy, 1965–1974; 413 cars (330 Series I, 83 Series II), 90 of them 7-litre.
• Chevrolet V8 engines: 5.4 l 327 with 224–261 kW (300–350 hp), 7.0 l 427 with 324 kW (435 hp); later 7.4 l Chevrolet 454 and 5.8 l Ford 351.
• Design: mechanicals by Giotto Bizzarrini, styling by Giorgetto Giugiaro at Bertone.
• Racing version A3/C: 22 made, 9th overall at Le Mans in 1965.

Iso Grifo at a glance: maker, production years (1965–1974), purpose

Development and production history

Renzo Rivolta commissioned the Grifo A3/L in 1963 as a faster, sportier companion to the Rivolta GT. Bertone showed the A3/L prototype at the 1963 Turin Motor Show, and Iso unveiled an unpainted A3/C competition version there too. The road car used the chassis of the GT 300 and entered production in 1965. That base car, the Iso Rivolta GT (IR 300) of 1962, was a luxury coupé styled by Bertone from Giugiaro's sketches and powered by a Chevrolet Corvette V8; with 221, 250 or 257 kW (300, 340 or 350 PS) it reached 205–258 km/h.

The partnership with Bizzarrini then broke down over the use of the Grifo name. Iso continued with the road-going Grifo GL, while Bizzarrini went on with the competition A3/C; only 22 A3/C cars were made before the split. Iso's own story ended in the 1970s. The company had listed on the New York Stock Exchange in 1973, and English Wikipedia names the cost of its Formula One team, falling sales, the 1973 oil crisis and strong rivals as reasons for its collapse. Iso stopped building cars on 31 December 1974.

Design and engineering

Giorgetto Giugiaro styled the Grifo at Bertone, and the shape changed little over nine years. The coupé is low: 1,200 mm high on a 2,500 mm wheelbase and 4,430 mm long. The first targa-top Grifo, car number 97, was shown at the October 1966 Turin Motor Show. In 1970 the Series II arrived with a sleeker nose and hidden headlights.

Under the body sits the chassis of the Iso GT 300, with the V8 at the front driving the rear wheels. Weights range from 1,430 to 1,610 kg depending on version, and Bizzarrini was responsible for the mechanical design. Another Bertone designer, Marcello Gandini, later designed the Iso Lele.

Engine and drivetrain: Chevrolet and Ford V8s

The standard engine was the 5.4-litre Chevrolet 327 V8, with 224 kW (300 hp) in standard form and up to 261 kW (350 hp) in the stronger versions. English Wikipedia says the 327 car reached 110 km/h in first gear and could pass 275 km/h. In 1968 Iso added the 7.0-litre Chevrolet 427 Tri-Power L71, with an advertised minimum of 324 kW (435 hp) at 5,800 rpm; Iso claimed 300 km/h for this 7 Litri. The Series II IR-9 "Can Am" used the 7.4-litre Chevrolet 454, and from 1972 the IR-8 had a 5.8-litre Ford 351 V8.

Most cars had a Borg-Warner four-speed manual. A ZF five-speed was used in some targas and in 23 Series II cars, and a three-speed automatic was listed. With 324 kW and about 1,430 kg, the 7-litre car has about 227 kW per tonne. The power-to-weight calculator and the power converter put those figures against modern cars.

Iso Grifo specifications

Variants and derivatives: GL, 7 Litri, targa and A3/C

In service: the A3/C at Le Mans and the end of Iso

The A3/C was built by Piero Drogo's Sports Cars in Modena under Bizzarrini's supervision, on a much smaller budget than Ferrari's racing cars. At Le Mans in 1964, Edgar Berney and Pierre Noblet finished 14th overall despite a two-hour stop to repair the brakes. In 1965 an A3/C finished 9th overall.

English Wikipedia names the 1973 oil crisis, which cut demand for large-engined cars, as the main reason for the end. Iso went bankrupt in 1974. By then the Grifo had been joined by the Fidia saloon of 1968 and the Lele 2+2 of 1969, and from 1972 the range also used Ford V8s in the IR-6 Lele, IR-8 Grifo and IR-10 Fidia. Atelier Zagato revived the Iso Rivolta name in 2017, and the GTZ of 2019 onwards, limited to 19 cars, has 485 kW (659 PS) and a top speed of 298 km/h.

Preservation and collecting today

With 413 cars made, every Grifo is rare, and English Wikipedia describes them as desirable collectibles today. The rarest are the Series II targas (4 built) and the Series II five-speed cars (23). The 7-litre cars, 90 in all, are the most powerful. No reliable public price data in euros was found for this article, so no market values are given.

Which Grifo to choose:

• For the original shape: a Series I GL with the 327 V8.
• For the most power: a 7 Litri with the 427.
• For open-air driving: one of the 14 Series I or 4 Series II targas.
• For racing history: an A3/C, the Le Mans car.

More Italian grand tourers are in the 1960s classics and the classic cars section. Iso models are listed in the Iso catalogue.