The 5300 GT stems from a long and complicated relationship between Bizzarrini, Giugiaro at Bertone and Renzo Rivolta. These three worked together to create the Iso Rivolta 300, a flagship car for Iso. Due to sporting nature of the chassis and the reliability of its Corvette V8 power, Bizzarrini wanted to go endurance racing but Rivolta, who owned Iso, did not agree.
By 1963, Rivolta was finally convinced to finance the development of a more sporting Iso Rivolta. The result was the precursor to the 5300 GT, the Iso Grifo. At the 1963 Torino Motor Show, both the competition Grifo A3/C and a a road going 2 + 2 Grifo A3/L, were displayed. Both Grifos concepts were styled by Giugiaro at Bertone, used the same chassis and the same engine. Immediately after the successful show, both versions of the Grifo were put into production.
After the death of Renzo Rivolta in 1965, the relationship between Bizzarrini and Iso ended with only 25 Grifos built. Bizzarrini then acquired the necessary parts and finish 50 cars himself. Without Iso, all cars after chassis #0224 were named Bizzarrini 5300 GTs and finally Bizzarrini's name graced his design. The Iso Grifo AC3/C and Bizzarrini 5300 GT were very much the same product.
Bizzarrini offered the 5300 in two variations. As a road car Strada, more interior appointments, including ventilation, were standard. After moderate tuning, the Chevrolet V8 engine provided 365 hp, keeping it well ahead of Ferrari's 275 GTB. Top speed was 233.4 kph / 145.0 mph. 0 - 60 mph took approx. 6.3 seconds.
For the racing client, or adventurous customer, Bizzarrini offered the racing car Corsa version with a tighter steering ratio, hot engine, lightweight body and no seat belts. This version had a 405 hp version of the Corvette V8. No two cars are exactly alike.
Production of the 5300 GT lasted until well into 1968 and a combined total of 115 examples were produced. Of these, 104 were Stradas. it’s thought that approximately 70 Stradas were build with the full aluminium alloy body – these cars are the most highly valued by collectors and their prices at auction have been seeing a significant bump in recent years. Bizzarrini also produced three 5300 SI Spyders with a Targa body. (ultimatecarpage.com, silodrome.com & supercars.net)
5300 GT Strada
This green 1968 Bizzarrini 5300 GT Strada Alloy was sold for €548.800 (approx. $734.887) in May 2014. (rmauctions.com)
5300 GT Corsa
The bodywork was constructed of glass-fiber, the covers of the headlights were made of plastic, and some had a leather retaining strap kept the hood in place. The interior featured few amenities and whatever was not needed was removed. About 10 units made. (conceptcarz.com)
Iso Grifo A3/C (1963 - 65)
Only 7 made.
Below (Red) Iso Grifo (Silver) Bizzarrini 5300 GT Strada
(Photos from autowp.ru, ultimatecarpage.com, supercars.net,
boldride.com, topspeed.com, mycarquest.com & rmauctions.com)