Guide: Iso Grifo A3/C
Background
When Milanese industrialist Renzo Rivolta decided to expand his empire into the lucrative market for high end motor cars, he recruited two of the most respected names in the business: renowned engineer Giotto Bizzarrini was brought on board to design everything under the skin while Carrozzeria Bertone took charge of styling and body building.
The resultant Iso IR that emerged at the Turin Motor Show in October 1962 was a critically acclaimed two-door Coupe with a spacious four-seat cockpit. Unlike its domestic rivals from Ferrari and Maserati, the Iso was powered by a Chevrolet engine and many of the remaining components were sourced from established suppliers.
By the spring of 1963, production of the Iso IR was underway and Rivolta turned his attention to a pair of high performance two-seaters both of which would be marketed as the Iso Grifo. One, the A3/C (or Competizione) would be a racing car to promote the Iso brand internationally. The other, the A3/L (or Lusso) would be a luxuriously equipped Gran Turismo.
To design the two Grifos, Rivolta once again turned to Giotto Bizzarrini who was commissioned to develop both cars from his Bizzarrini Prototipo concern in Livorno. The ex-Scuderia Ferrari man would also manage Iso’s competition programme.
The A3/C was styled by Bizzarrini in collaboration with Giorgetto Giugiaro who was chief designer at Bertone. Fabrication of the A3/C’s lightweight aluminium bodywork was undertaken by Carrozzeria Sports Cars of Modena run by Piero Drogo.
The A3/L (covered separately) had a completely different steel bodyshell that was designed and manufactured at Bertone’s Turin facility.
Prototypes of the A3/C and A3/L were both unveiled at the Turin Motor Show in October 1963.
This first A3/C (chassis B-0201) was completed at the last moment. Iso presented the car in bare aluminium bodywork that had been polished using cork mats on the end of an electric drill to give an unusual swirled effect.
Two versions of the A3/C would be offered to customers: a Corsa for competition use and a Strada for road use.
Chassis
The A3/C was based around a tubular steel chassis to which light alloy centre sections and the bodywork were riveted in place to form a semi-monocoque arrangement.
To optimise weight distribution, the engine was mounted so far back in the chassis that access to the ignition and distributor was via a trap door located on top of the dashboard.
Like the A3/L, the A3/C had a 2450mm wheelbase.
Independent front suspension was via double wishbones. At the back was a de Dion axle with twin radius arms and a lateral Watt’s linkage. Coil sprung telescopic Koni dampers were fitted all round and there was also a front anti-roll bar.
Brakes were Dunlop Mk9 discs with magnesium two-piston Campagnolo calipers. The outboard front discs had a 296mm diameter. The rears measured 305mm and were located inboard of the differential.
Campagnolo also supplied Iso with 15-inch diameter centre-lock cast alloy wheels (6-inches wide front and 7-inches wide rear). These were originally shod with either Dunlop R6 / R7 racing tyres (Corsa) or Dunlop SP / Goodyear Blue Streak rubber (Strada). Up to 9-inch wide rear wheels were available for competition use.
In his pursuit for perfect weight distribution, Bizzarrini devised a 145-litre fuel system that comprised two side-mounted saddle tanks joined by a third located directly behind the seats. The effect was a less than 1% transfer in weight distribution as the tanks emptied.
Engine / Gearbox
Rather than design and build his own motors from scratch, Renzo Rivolta chose to install large capacity, ultra-reliable and extremely powerful American V8s in his cars.
The A3/C was powered by a cast-iron 327 cubic-inch Chevrolet V8 sourced from General Motors.
Although displacement was kept at 5354cc (thanks to a bore and stoke of 101.6mm and 82.6mm respectively) upon arrival in Italy, these pushrod-operated overhead valve motors were dismantled, blueprinted and fitted with a host of special parts to include a ribbed alloy sump.
The fuel-feed system also came in for attention with carburettors preferred to GM’s injection arrangement.
The A3/C Strada ran an 11.0:1 compression ratio with a Carter four-barrel carburettor. Peak output was 365bhp at 6000rpm and 376lb-ft at 3500rpm.
For the A3/C Corsa, compression was dropped to 10.5:1 to reduce detonation symptoms. Four twin choke Weber 45 DCOE sidedraught carburettors were installed along with a cross-over ram induction system. Other hop-up parts included polished ports and combustion chambers, high carbon connecting rods, high-lift camshafts and a free flow exhaust system.
Peak output for the Corsa was 405bhp at 6000rpm and 370lb-ft at 3600rpm.
Transmission was through a four-speed Borg Warner T10 gearbox with a single dry-plate clutch and Salisbury 4HU final drive with limited-slip differential.
A choice of five gear ratios was available: from 2.51:1 for Le Mans through 2.88, 3.07 and 3.31 all the way up to 3.54 for hillclimbs.
Bodywork
Together, Giotto Bizzarrini and Giorgetto Giugiaro created one of the most exotic front-engined bodies of the early 1960s. Their rakish, low slung design incorporated all the latest aerodynamic understanding such as covered headlights, flattened sides and a Fastback cabin with truncated Kamm tail.
The A3/C was peppered with elegant cooling solutions such as twin front nostrils plus vents behind all four wheels and along each of the sail panels. Engine cooling was further aided by massive cut outs on the hood and a shallow intake carved from the front apron (inboard of additional ducts for the brakes).
Strada variants normally came with wind-down glass windows, opening quarterlights and glass headlight covers shrouded by attractive chrome bezels. The Corsa had sliding Plexiglas side windows and simplified headlight covers fashioned from the same lightweight material.
Both versions used a flat Plexiglas rear windscreen and came with an exposed fuel filler cap mounted atop the right-hand rear fender.
Fabrication was by Carrozzeria Sports Cars of Modena who attached the aluminium panels to the chassis by way of several thousand exposed rivets.
Interior
In the cockpit there were few concessions to comfort.
Once over the wide sills, occupants were greeted by single-piece bucket seats divided by an enormous transmission tunnel.
Behind the wood-rimmed steering wheel with its three highly polished-and-vented spokes was a simple crackle black dash. The otherwise flat dash top featured three discreet cowls for the small oil temperature, oil pressure and water temperature gauges located directly ahead of the driver. Larger read outs for road and engine speed were positioned centrally.
The seats were upholstered with plain bolsters and fluted centres. The transmission tunnel, rear bulkhead and parcel shelf were diamond-patterned.
Strada versions came with carpeted floors and sidewalls, properly trimmed door panels with storage pockets, a fluted headliner, an improved heating / ventilation system and extra sound insulation.
Options
As a result of its hand-built nature, the A3/C could be ordered with any combination of Corsa or Strada features.
In addition to the aforementioned gear ratios, customers could specify leather upholstery and head rests for the seats. They could also choose from two steering ratios and four final drive ratios (2.88, 4.35, 5.53, 7.32:1).
Weight / Performance
The A3/C Strada weighed 1270kg. With a standard 2.88:1 rear axle ratio it had a 0-62mph time of 6 seconds and top speed of 162mph.
Thanks to less comfort equipment, the Corsa tipped the scales at 1220kg. Performance figures with the aforementioned axle ratio were a top speed of 186mph and 0-62mph time of 5.1 seconds.
Production Changes
During the course of production, myriad changes were made to the style and location of the various ducts and vents scatter around the A3/C’s bodywork. Decorative bumpers were also introduced and the flat rear screen was later switched to a more elaborate curved item that extended down into the sail panels.
1964 Racing Season
As had been the case since 1962, the FIA’s de facto World Sportscar Championship of 1964 (the International Championship for GT Manufacturers) was open to production-based Grand Touring cars that had met a minimum production requirement of 100 units.
Taking place alongside was the International Prototype Trophy which was decided on the outcome of four of that year’s races (the Sebring 12 Hours, Targa Florio, Nurburgring 1000km and Le Mans 24 Hours). Prototypes were permitted to attend several of the other events, but were not eligible for points.
Unfortunately for Iso, by the time the ‘64 season kicked off, the A3/C had not come close to meeting the 100-car production run required to compete in the Grand Touring class. Had the homologation target been met, the A3/C would have been pitched against the likes of the second series Ferrari 250 GTO and Shelby Cobra Daytona.
Instead, the A3/C had to run in the Prototype category alongside purpose built racing cars such as Ferrari’s 3.3-litre 275 P and 4-litre 330 P. Rivals for the Iso in the over five-litre Prototype category would include Chevrolet’s Corvette Grand Sport, the occasional Lola Mk6 GT and Maserati’s fearsome Tipo 151.
1964 Sebring 12 Hours
The A3/C made its competitive debut at the Sebring 12 Hours which took place on March 21st 1964. A brand new Corsa (chassis B-0202) was shipped out to Ed Hugus on behalf of the car’s new owner, William McLaughlin. Hugus and McLaughlin were joined in B-0202 by co-driver, Enus Wilson.
Having arrived in Florida wearing a handsome white colour scheme with a thin blue centre stripe, the Iso was further accessorised with additional blue and red stripes to the right-hand front fender during the course of practice.
As Campagnolo’s cast alloy wheels had not been sufficiently tested, the A3C ran on wire wheels at Sebring. B-0202 would contest over three-litre Prototype class alongside a quintet of Ferrari P cars, three Corvette Grand Sports, a works seven-litre Cobra and the Mecom Racing Team’s Lola’s Mk6 GT.
1964 was the first time that grid slots had been decided on practice times at Sebring. B-0202 lined up 29th out of 66 starters but had dropped to 32nd after the first round of stops.
Unfortunately, the Iso’s transmission blew during the fourth hour which ruled out any chance of a fairytale debut. Nevertheless, a new gearbox was fitted in the pits and B-0202 rejoined the race ten minutes from the end. Hugus, McLaughlin and Wilson were ultimately classified 39th overall and seventh in the over three-litre Prototype class.
Despite the disappointment of Sebring, William McLaughlin went on to have a very good season with his A3/C; thanks most notably to a pair of class wins at Mid-America, he claimed the 1964 SCCA C Modified Midwestern championship.
1964 Le Mans Test
The next appearance for an A3/C came at the annual Le Mans Test which in 1964 took place over the weekend of April 18th and 19th. Iso ran the ex-Turin Motor Show car (chassis B-0201) which by this time had been painted red.
As per B-0202 at Sebring, B-0201 attended the Le Mans Test on wire wheels.
The Grifo (which ran under an Auguste Veuillet entry) drew many positive comments for its beautiful finish, but did not seem particularly quick.
Pierre Noblet and Fernand Tavano were recruited to drive; they posted a best lap of 4 minutes 13.4 seconds which was good enough for ninth fastest overall and fifth in the over three-litre Prototype category.
1964 Nurburgring 1000km
After its run-out at the Le Mans Test, B-0201 was back in action as an official entry for the Nurburgring 1000km six weeks later (May 31st). On this occasion, the car was shared by Pierre Noblet and Edgar Berney. It was now on Campagnolo alloy wheels which had been found to be secure for competition use.
Sadly, practice for the 44 lap event was marred by the fatal accidents of Brian Hetreed (who crashed his Aston Martin DP214 at Keffelchen) and Rudolf Moser (whose Porsche 904 went out of control at Tiergarten).
Nevertheless, the race went ahead as planned and the Iso (which at 1203kg was the heaviest car in attendance) qualified 32nd on the mammoth 81 car grid.
Proceedings got underway at 9am and Noblet made a storming start to lie ninth by the end of lap one. However, B-0201’s engine was a little down on power and although the Grifo had a trouble-free run, it lacked outright pace.
By the time the chequered flag fell, Noblet and Berney had dropped to 19th overall which was good enough for second in the over three-litre Prototype class behind the works Ferrari 275 P of Scarfiotti / Vaccarella which won the event outright.
Iso sells B-0201 to Antonio Finiguerra
Shortly after the Nurburgring 1000km, Iso sold chassis B-0201 to Italian privateer, Antonio Finiguerra, who later that year went on to campaign the car in a couple of hillclimbs, the Pries von Tirol at Innsbruck (eighth overall and second in class) and the Trofeo Bettoia at Monza (seventh overall and third in class).
Finiguerra was subsequently joined in the car by Regis Frassinet for the 1965 Monza 1000km where B-0201 appeared as a factory entry (owing to alack of works cars) and placed 13th overall (seventh in class). B-0201 was then sold to Swiss privateer, Pierre de Siebenthal, who continued to campaign the car until the end of the ‘65 season.
1964 Le Mans 24 Hours
Iso ran a brand new A3/C at the Le Mans 24 Hours (June 20th and 21st); chassis B-0207 was entered for Noblet / Berney who had driven together at the Nurburgring three weeks earlier.
Frustratingly, a planned-for overdrive that was supposed to be fitted to B-0207’s gearbox had not materialised which meant the car ran with too low a top gear. It was thus limited to just 172mph and the drivers were forced to lift down the ultra fast Mulsanne Straight.
Despite this, B-0207 still managed to qualify 16th on the 55 car grid; a top ten grid slot may have been possible if the Grifo had topped out closer to its expected 190mph maximum.
The race got underway at 4pm and by the end of first hour B-0207 occupied 16th position.
Noblet and Berney had moved into twelfth by the six hour mark, but shortly after 10pm there was a terrible accident when Peter Bolton’s AC Cobra left the road between Arnage and White House. Bolton’s car was struck by Giancarlo Baghetti’s works Ferrari 275 P which then shot into a ditch.
After the two drivers were taken away shaken but unhurt, the officials were horrified to find that three people had been killed while spectating in a prohibited area.
As ever, the race continued and the Iso finally broke into the top ten at 1:30am on Sunday morning.
By 4am it had risen to ninth.
However, a two-hour pit-stop then ensued which dropped Noblet / Berney down to 21st by 7am; while carrying out a routine brake pad change, one of the pads fell into the caliper which meant Iso’s mechanics had to remove the entire rear axle.
Undeterred, the drivers pressed on for the remainder and steadily regained ground. B-0207 ultimately recovered to claim 14th at the end which was good enough for fourth in the over three-litre Prototype class behind the trio of works Ferraris that claimed first, second and third overall.
1964 Reims 12 Hours
Following on from its 14th place finish at Le Mans, Iso entered chassis B-0207 for the Reims 12 Hour race on July 5th.
The Reims event, which started at midnight and ran until noon, was another round of the 1964 World Sportscar Championship but one for which Prototypes were not eligible to score points.
Noblet and Berney qualified twelfth of the 37 starters and had moved up to eleventh by the end of the first hour.
They continued to move through the field and at 3am were in eighth. However, by 5am their race was over when a bent valve forced B-0207 into retirement.
Graham Hill and Jo Bonnier went on to secure victory in their Maranello Concessionaires Ferrari 250 LM (which ran in the same over three-litre Prototype category as the Iso).
1964 St. Ursanne-Les Rangiers Hillclimb
On August 23rd, Iso entered Edgar Berney to drive B-0207 at the St. Ursanne Hillclimb in north-west Switzerland.
The 5.2km route rose through an elevation of 350m and, although the 1964 event formed part of the European Touring Car Championship, the Prototype categories were not well supported.
As a result, the big Prototype class proved a walkover for Swiss native Berney who easily won the over three-litre group.
1964 Sierre Montana-Crans Hillclimb
One week later, the Sierre Montana-Crands Hillclimb played host to a round of the World Sportscar Championship for which Edgar Berney was again entered in B-0207.
Dubbed the Swiss Mountain Grand Prix, the event comprised an 11km course that rose through an elevation of 820m.
Berney posted tenth best time overall and claimed second in the over three-litre Prototype class behind outright winner Ludovico Scarfiotti in a works Ferrari 250 LM.
1964 Paris 1000km, Montlhery
The 1964 World Sportscar Championship concluded with the Paris 1000km race at Montlhery on October 11th.
For the first time, Iso had a brace of Grifos in attendance: B-0207 for Mario Casoni / Odoardo Govoni (who qualified 18th) and a brand new machine, B-0208, for Pierre Noblet / Edgar Berney (who qualified eighth).
The 37 starters got underway in dry but blustery conditions. However, a couple of hours in, rain began to fall heavily and the circuit soon became treacherous.
With water having got into its fuel system, B-0208 began to experience persistent delays.
Then on the 84th lap, another disaster struck when Peter Lindner’s Low Drag Jaguar E-type went into a slide when an engine seal ruptured. The Jaguar aquaplaned into the stationary Abarth Simca of Franco Patria which was about to return to the track. Both drivers and three marshals were killed in the accident.
The horrible conditions continued until the end and the race concluded amid a very sombre atmosphere. Casoni / Govoni came home eleventh overall (third in class) while the much delayed pairing of Berney / Noblet crossed the line in 21st position (fifth in class).
Victory went to the Maranello Concessionaires Ferrari 330 P of Graham Hill / Jo Bonnier which won the over three-litre Prototype category.
1964 Monza Trofeo Bettoia
Two weeks after the sad events at Montlhery, the A3/C made its final appearance of the year.
Monza was hosting the European Touring Car Championship finale on October 25th and, in support, a pair of races for Sports and GT cars were organised. The format saw a one hour preliminary on Saturday followed by a three hour final on Sunday.
Three Grifos were entered: the two works cars that appeared at Montlhery (B-0207 for Mario Casoni and B-0208 for Edgar Berney) in addition to Antonio Finiguerra who took part in his privately owned example (B-0201).
The one hour race for big-engined cars on Saturday saw the Maranello Concessionaires Ferrari 330 P of Ludovico Scarfiotti walk away from the opposition. Meanwhile, Casoni dealt magnificently with the GTO Ferraris and overhauled Ben Pon’s Porsche 904 GTS to claim second.
The three hour finale on Sunday played out in a similar fashion with Scarfiotti leading Casoni home. Finiguerra claimed seventh in his privateer A3/C, but Berney retired with engine trouble.
1965 Season
The 1965 season took place with much the same format and regulations as had been the case in 1964. However, the International Prototype Trophy (now re-branded as the International Trophy for GT Prototypes) was expanded from four to ten events.
1965 Sebring 12 Hours
The 1965 season kicked off with Iso’s ambitious plan to run two works cars at the Sebring 12 Hours on March 27th. A brace of brand new A3/C Corsas were dispatched to Florida: chassis B-0210 for Silvio Moser, Mario Casoni and Dave Greenblatt and chassis B-0214 which was allocated to Charlie Rainville and Mike Gammino.
To assist with the complicated logistics, Rino Argento was enlisted to help manage the operation at Sebring; Giotto Bizzarrini would look after B-0210 while Argento would manage the American-crewed B-0214.
An early difference of opinion between the two men occurred when Argento advised Bizzarrini to use Castrol brake fluid (which had a much higher boiling point than the Dunlop product), but Bizzarrini chose to ignore this advice.
Despite having been told not to push too hard in practice, Moser / Casoni / Greenblatt qualified 24th on the 66 car grid and Rainville / Gammino lined up 25th.
The race got underway at 10am in blisteringly hot conditions. However, things started badly when Rainville went off at the first corner on the opening lap in an attempt to avoid a pair of cars that had made contact ahead of him. B-0214 span onto the grass and into the catch-fence. Although damage was slight (a crumpled right-hand rear fender), a couple of spectators were injured during the accident.
In the sister car, Silvio Moser had early problems too; B-0210 was beginning to experience severe brake fade as its Dunlop brake fluid boiled and evaporated. During the second hour things came to a head when, on lap 16, Moser’s brakes failed completely as he approached the hairpin. B-0210 flew over a sandbank and into the spectator’s area where it slammed head-first at high speed into a stationary Volkswagen Beetle. With its front end pummelled-in, the brand new car was wrecked and three spectators were slightly injured.
By the halfway mark at 4pm, steady progress had seen Rainville and Gammino move B-0214 into the top ten.
However, shortly before 5:30pm, torrential rain arrived and in next to no time the track was awash. Lightning and thunder followed but the race continued.
Blinded by the deluge, Gammino (who was on the third lap of his second stint) lost control of B-0214 which aquaplaned and smashed sideways into the Mercedes-Benz bridge. The extraordinary impact saw B-0214 ripped in two behind the doors. Miraculously, Gammino (who had not fastened his safety belts) walked away without injury.
Neither B-0210 or B-0214 returned to Italy. The wrecked remains were sold off and eventually grafted together by a subsequent owner to make one complete car.
1965 Le Mans Test
With the two brand new cars assembled for 1965 having been written off, chassis B-0207 was wheeled out to attend the Le Mans Test which took place over the weekend of April 10th and 11th. This was the car that had been campaigned at Le Mans, Reims, Montlhery and the Monza Trofeo Bettoia in 1964 as well as a couple of hillclimbs.
B-0207 appeared in much the same trim as 1964. It was allocated to Pierre Noblet, Willy Mairesse, Regis Frassient and Jean de Mortemart who ultimately posted eleventh fastest time.
B-0207 was also quickest of the over over five-litre Prototypes in attendance. The only other car in its class was the Maserati 151/4 of Lloyd Casner, Masten Gregory and Guerino Bertocchi. Unfortunately, during the wet Saturday session, Casner was killed when he lost control at around 170mph down the Mulsanne Straight.
1965 Monza 1000km
B-0207 was back in action two weeks later for the Monza 1000km (April 25th). In order to run a two-car team on home soil, Bizzarrini convinced Antonio Finiguerra to attend with chassis B-0201 which appeared as an official works entry with factory driver Regis Frassinet accompanying Finiguerra behind the wheel.
Meanwhile, B-0207 was allocated to Pierre Noblet and Mario Casoni who qualified 14th on the 33 car grid. Finiguerra / Frassinet started 20th.
At the ten lap mark, Noblet had moved up to ninth position and B-0207 was looking good for a strong finish.
Unfortunately, disaster struck on lap 33 when Tommy Spychiger suffered brake failure in his Scuderia Filipinetti Ferrari 365 P. Travelling on the flat out approach to Parabolica, the car somersaulted into the trees and poor Spychiger was decapitated. Georges Filipinetti immediately withdrew his other cars from the race.
By the halfway point, Noblet / Casoni were lying fifth behind the two works Ferrari prototypes and Ford GTs. They then found themselves promoted to fourth when a suspension failure caused one of the Fords to drop out. However, B-0207 was subsequently passed by the Racing Team Holland Porsche 904 GTS of Ben Pon / Rob Slotemaker.
Nevertheless, fifth overall and fourth in the over two-litre Prototype class was a strong result for the veteran B-0207. Victory in the Prototype category went to the Mike Parkes / Jean Guichet works Ferrari 275 P2. Another factory Ferrari placed second and the sole remaining Ford was third.
Finiguerra / Frassinet placed 13th overall and seventh in class.
1965 Spa 500km
Following its strong finish at Monza, B-0207 was wheeled out to contest the Spa 500km race on May 16th.
Pierre Noblet was brought in to drive the 36 lap race single-handedly and qualified ninth out of the 27 starters.
At two thirds distance, all the cars had made their final pit stops and Noblet was lying eighth.
Two laps later though there was yet another fatal accident. Driving an Ian Walker Racing Alfa Romeo TZ, Tony Hegbourne had something break on the Masta Straight which caused his car to flip end over end at about 125mph. The Alfa left the track and hit a house.
Hegbourne suffered a broken spine, a broken arm, a punctured lung, a broken leg and head injuries. Having been admitted to an intensive care unit in Verviers, he was subsequently transferred to Stanmore in England died of his injuries on July 1st.
As ever the race continued and by the time the chequered flag fell, Pierre Noblet had moved B-0207 up to seventh overall which was good enough for this in the over two-litre Prototype category. The class and overall victory went to the Ecurie Francorchamps Ferrari 250 LM of Willy Mairesse while another 250 LM (that of David Piper) claimed second.
1965 Nurburgring 1000km
One week after the race at Spa, Nurburgring played host to its annual 1000km contest (May 23rd).
For this event, B-0207 was joined by a much-needed brand new A3/C: chassis B-0222.
Significantly, B-0222 was the first A3/C equipped with independent rear suspension as opposed to the original de Dion arrangement. It also wore a fibreglass instead of aluminium body which had been fabricated at Vincenzo Catarsi’s shipyard in Livorno and then refined at Carrozzeria BBM.
However, the new car failed to set a time in practice which meant Mario Cabral and Teodoro Zeccoli were forced to start from the back of the 63 car grid.
Meanwhile, Pierre Noblet was joined by Wittigo Einsiedel in B-0207 which qualified in 32nd position.
The race got underway at 9am, but Cabral came in after just two laps with iffy brakes. Three laps later, B-0222’s maiden appearance ended with broken suspension.
The sister car of Noblet / Einsiedel then ran out of fuel on lap 16.
A short while after Iso’s weekend had been brought to a premature end, lap 19 saw the Alfa Romeo TZ of Honore Wagner leave the road at the Kallenhardt section. The car (which Wagner was sharing with its owner, Nicolas Koob) crashed into a ravine and landed on its roof. Poor Honore Wagner sustained fatal head injuries and was pronounced dead at the scene.
1965 Le Mans 24 Hours
Just one A3/C attended the 1965 Le Mans 24 Hours (June 19th and 20th). Unsurprisingly it was the lightweight glassfibre-bodied example with independent rear suspension that had debuted four weeks earlier at the Nurburgring: chassis B-0222.
Giotto Bizzarrini drove the still low mileage car to la Sarthe where, for the first time in Le Mans history, the first day of practice had to be abandoned owing to tornado that swept across the region. However, thereafter the event took place in perfect conditions.
Other than B-0222 (which was allocated to Jean de Mortemart / Regis Frassinet), the only other contenders in the over five-litre Prototype class were a handful of Ford GTs and a solitary Maserati Tipo 65.
The Iso qualified 24th of the 51 starters, but dropped back early on with brake problems.
It subsequently had a trouble-free run though and by 10am on Sunday morning (when just 18 runners remained), de Mortemart / Frassinet had moved up to tenth.
They gained another position during the final six hours and ultimately crossed the line in ninth overall, winning their class, after 24 hours of racing at an average speed of 169kmh. For comparison, the race-winning NART Ferrari 250 LM of Jochen Rindt / Masten Gregory / Ed Hugus had averaged 195kmh.
Immediately afterwards, Giotto Bizzarrini drove B-0222 back to Livorno.
1965 Reims 12 Hours
Fresh from its class win at Le Mans, B-0222 attended the Reims 12 Hour race two weeks later (July 4th) where it was joined by B-0207.
The old alloy-bodied de Dion example qualified twelfth in the hands of Pierre Noblet / Mario Cabral while the newer GRP-bodied IRS machine of Jean de Mortemart / Regis Frassinet was two places back in 14th. The Isos would be up against a fleet of Ferrari prototypes to include 365 P2, 330 P and 250 LM tipos.
For 1965, the traditional midnight start at Reims was brought forward to 11pm.
Noblet got a great start and was lying sixth at the end of lap one. However, he was then passed by some of the faster cars and had dropped back to tenth by lap five. Soon after, B-0207 was in the pits for the first of a series of stops to try and eliminate a slipping clutch.
Unfortunately, the race was then marred by a fatal accident around midnight when the Ecurie Francorchamps Ferrari 250 LM of Gerard Langlois van Ophem went off at one of the very fast bends after Gueux and killed two marshals. Langlois van Ophem emerged from the crash without injury.
Both Grifos then retired in quick succession: B-0207 with a badly oiled clutch and B-0222 with a blown head gasket.
Victory went to the NART Ferrari 365 P2 of Pedro Rodriguez / Jean Guichet.
1965 Mont Dore Hillclimb
On August 15th, chassis B-0222 was entered for Maurice Trintignant to drive at the Mont Dore Hillclimb in central France. The ex-Ferrari F1 driver and two-time Monaco Grand Prix winner had won the 5km Mont Dore event in 1964 with his BRM P57.
For the 1965 running (which was a round of the French Hillclimb Championship), Trintignant drove B-0222 to eighth fastest time overall and second in class.
1965 Austrian GP, Zeltweg
Two weeks after its outing at the Mont Dore Hillclimb, B-0222 was back in action at the Austrian Grand Prix which took place at the Zeltweg airfield in Styria (August 22nd).
B-0222 was entered for Chris Amon to drive in the 200 mile 100 lap race and qualified eighth.
A second fibreglass-bodied independent rear suspension A3/C was also on hand for its maiden event: chassis B-0226 which was allocated to Bob Bondurant who qualified 13th.
Of the 14 starters, the pair of Isos were noted for their poor finish.
Both Grifos moved up the order as some of the faster cars retired, but Bondurant in particular was hampered by obtrusive bodywork on the bumpy airfield circuit.
Amon went on to finish fourth overall (fourth in the over two-litre Sports class) while Bondurant came home in seventh (sixth in class).
Renzo Rivolta & Giotto Bizzarrini Split
Although the A3/C had shown much promise during its 18 month competition career, trouble was brewing behind the scenes.
The A3/C had been developed, marketed and raced entirely at Renzo Rivolta’s expense. However, Giotto Bizzarrini had supplied nearly every A3/C with a Bizzarrini badge and most of the car’s competition outings had been made under Bizzarrini Prototipo entries. Inexplicably, it also transpired the Giotto Bizzarrini had registered the Grifo trademark for himself.
At the end of August 1965, an exasperated Renzo Rivolta ended his association with Bizzarrini.
The termination agreement saw Bizzarrini hand over the Grifo trademark in exchange for the sole production rights to the A3/C and enough component parts to construct 50 cars under whatever name he desired.
With the cost of an expensive racing programme now down entirely to him, Giotto Bizzarrini primarily switched his focus to the production of road-going variants which were marketed as the Bizzarrini 5300 GT (covered separately). His appetite for competition was satisfied with the development of an out-and-out Prototype for the 1966 season (the Bizzarrini P538).
End of Production
A3/C production ended after between 22 and 34 cars had been completed (depending on whether they are considered Iso or Bizzarrini products).
Text copyright: Supercar Nostalgia
Photo copyright: Iso, Paul Rainville, Technisches Museum Wien - https://www.technischesmuseum.at/en The Henry Ford Archive - https://www.thehenryford.org/
