Iso Spa in Bresso was already well known for producing the extremely well built and fast Iso Rivolta IR300; a sleek looking 2+2 Coupe based on a Chevrolet Corvette power train. After leaving Ferrari, in 1961 Giotto Bizzarrini set up “Prototipi Bizzarrini” in Livorno, Tuscany where he designs and consults for Marques like ATS, Lamborghini and Iso Rivolta. In 1963 he designed the Iso Grifo A3/L (L for Lusso) for Renzo Rivolta, who was looking for a follow-up to his Iso Rivolta GT. The body was designed by Giorgetto Giugiaro at Bertone, while Giotto put his expertise in the mechanicals. Giotto figured there would also be a demand for a race version of the Grifo and came up with the A3/C (C for Corsa) with a dramatic modified alloy body. He later dubbed it his “Improved GTO,” as he had been the designer for the 250 GTO when he had worked for Ferrari. The engine was moved back about 0.4 meters, making the A3/C one of the first front-mid-engined cars ever built. To adjust the timing, you actually had to take out a piece of the dash! Both cars were being built simultaneously.
That same year Bertone showed the Grifo A3/L prototype at the Turin Auto Show, while Iso showed off the (partly unfinished) competition version; the Iso Grifo A3/C. Both were overwhelmingly successful. Although design changes had to be made to the prototype, Iso concentrated on getting the Grifo A3/L ready for production. The car got a light facelift that made it less aggressive but turned it into possibly the most elegant-looking Gran Turismo (GT) supercar ever produced. This “street” Iso Grifo GL received the fast, modified but very dependable Chevrolet Corvette’s 327 V8 (5.4 L) engine—either in 300 or 350 hp—coupled to a Borg-Warner 4-speed toploader. These engines were ordered in the US, but were completely taken apart and blueprinted before they were put in; as they did with the Iso Rivolta GT. With over 400 horsepower and a weight of less than 2200 pounds, the vehicle was able to reach speeds over 275 km/h.
While Renzo Rivolta focused on the A3/L; Giotto tried to promote the A3/C—making for some tension between the two. This meant that the Grifo GL was being produced at Bresso and the A3/C at Piero Drogo’s Sports Cars of Modena under Giotto’s strict supervision. In 1964 the prototype Grifo A3/C raced at Le Mans (Edgar Berney/Pierre Noblet), running well until brake problems required a two hour pit stop. The car then resumed the race, finally finishing in 14th place; an encouraging result for a brand-new car. Only 22 examples of the Bizzarrini Grifo A3/C were constructed before a disagreement between Renzo and Bizzarrini ended the cooperation.
Finally in 1965 Giotto Bizzarrini and Renzo Rivolta split ways and this set the stage for a separated production of the “street” Grifo GL and the “competition” Bizzarrini A3/C. Giotto refined his A3/C and this eventually turned out to be his famous line of Bizzarrini 5300 Stradas and Corsas. From here on the “Grifo” name was lost in connection to Bizzarrini.
If we follow this parallel line of cars, Bizzarrini continues to build both Bizzarrini Stradas and Corsas and had the alloy bodies (put together with more than 10,000 rivets!) built by BBM of Modena. In 1966 he introduces a scaled down version; the Bizzarrini 1900 “Europa” which is first shown in 1967. Most of these cars got a hot version of the Opel 1900 engine, some are known to have Alfa Romeo engines. Only about 17 Europa’s were ever built, making it one of the rarest of his creations. Even rarer is the Barchetta version, the P538 with only three ever produced. A total of around 155 Bizzarrini Stradas and Corsas were built before Bizzarrini closes down in 1969 after a bankruptcy; all remaining parts and cars were sold off and makes them prone to many “fake”-stories going around. A few fake Stradas and P538s are already accounted for, so a potential buyer should be very discriminating when a Bizzarrini is offered. As of today a TRUE Bizzarrini is one of the most sought after sports cars in the world, not only because of its rarity but mostly because of its aggressive beauty.
To get back to the “luxury” Iso Grifo, Renzo Rivolta gets awesome reviews about his Iso Grifo GL. The car developed 390 hp in its production form and could hit 110 km/h in first gear! Renzo Rivolta also shows a one-off Grifo A3/L Spyder at the Geneva auto show and because this stayed a one-off this particular car is the most sought-after Iso ever as of today (2006). Its whereabouts are known, but the owner keeps it in unrestored condition stored away from the public. The full blown production of Iso Grifo GL starts in 1965 and customers are very happy with their cars, especially the combination of elegance and performance. In October 1966 the very first Grifo (car #97) with Targa Top is shown at Turin, this by Pavesi built version sported removable stainless roof panels and a zip-out rear window. This was one of 14 Targa’s ever built, a very desirable body style for collectors.
In 1968 the Grifo 7 Litri was introduced, this car got the spectacular Corvette L71 (a Tri-Power version of the famous Corvette 427) Big Block. This (Seven liter) power plant required many changes to the car to fit and a hood scoop was needed because of the height of this engine. It produced 435 hp at 5800 rpm and the factory claimed it could reach a top speed of 300 km/h. This particular, very first 7 Litri is still lost and is subject to many car lover’s dreams. Many think it got scrapped, though.
Then, in 1970 a well-overdue styling change is made to the nose section of the car and the Grifo Series II was born. This car got a sleeker look and hide-away headlights. While the original Series I was one of the most beautiful GT’s ever built, the new lines were perfect and the Grifo Series II became a timeless masterpiece with an even more aggressive look. In this new Series II, there were only 4 Targa’s built and when they switched from 427 engines to the newer 454 the IR-9 “Can Am” version was born. This engine was not as fast as the 7 Litri and production stopped in 1972. The Series II 7 Litri are extremely rare and are at the same time very comfortable AND very brutal machines to drive.
In 1972 Iso started to use Ford Boss 351 (Cleveland 4BBL) engines and these cars (Grifo IR-8) are recognized by their taller hood scoop which makes them look very aggressive. This version was the swan song version of the Iso Grifos, Iso S.P.A. had to close its doors in 1974. Main reason was the oil crisis. The Interior of the Grifo didn't change much during all its years of production as it simply was one of the best finished and most beautiful on the market.
All Grifos are extremely desirable today because of their rarity; beauty and un-complicated mechanicals, so most surviving cars are either restored or in the process of being restored. A former employee of Iso, Mr. Roberto Negri runs a small Company in Clusone, Italy where Grifos from all over the world are being restored to original specifications.
In the total there were 322 Series I and 78 Series II cars built for a total of 400 Grifos. 90 were 7 Litri but when it comes to rarity the Series II 5-speeds (23 units) and the Big Block Targa (1 unit) are the rarest and most sought after.