Hailed by many as the most beautiful car ever to come out of Japan, The Mazda RX-7 took seventeen years of development before it finally appeared on the streets in 1978.
Without the perseverance of a team of Japanese motor engineers and designers under the leadership of Kenichi Yamamoto, in the development of the Wankel or rotary engine, this stunningly designed, high performance sports car, would never have happened.
In 1961 the Japanese Company Toyo Kogyo, later to be renamed Mazda, licensed from the patent owners NSU-Opel of Germany, the full rights to develop a new rotary engine.
The Rotary engine was named after its inventor Wankel and had no pistons or crankshaft as such, but consisted of a simple fuel injected rotor blade that span around a central drive-shaft that was connected to a rear wheel differential for drive.
In theory the rotary engine is far superior, through its simplicity in design, than a conventional piston combustion engine, with much less moving parts to go wrong and direct drive power output.
Yamamoto's team at Mazda set to work on developing a rotary engine that would overcome the problems of loss of compression, exhaust, and the overheating of the rotor blades tips, that had limited Opels success at developing the technology in the 1950's.
After success with earlier RX models the RX-2, RX-3 and RX-5 and despite financial problems at the company, Mazda finally came up with the larger 12A engine which was fitted to the new Mark 1 RX-7 built from 1978 until 1980 and the series 2 built from 1981 to 1983.
The Mazda Rx-7 was a two seater plus two hardtop sports coupe, curvaceous and aerodynamic and it immediately caught the imagination of the motoring world which globally hailed it as an instant design classic. The design of the car was built entirely around the engine and exhaust configuration.
A bi-rotor engine putting out what was seen as equivalent of just 550 bhp per rotor the 12A in the RX-7 was capable of speeds of over 130 mph and with high low-end torque reached from 0 to 60 mph in just 6.3 seconds. Officially its bhp was just 100 horse power but given how light the car was, it was often described as like driving a skateboard, the power to weight ratio gave it an output equivalent to 230 bhp.
Exhilarating to drive because of the smoothness inherent in the movement of the Wankel rotary engine, little vibration or shaking was felt at high engine speeds. An alarm was fitted to the rev counter to warn the driver when the 7000 rpm redline was approaching. If you exceeded it or did not heed the alarm the engine would cut out to protect the ceramic rotor tips from overheating.
The car was expensive to run, the engine consuming around 20 miles to the gallon but at half the price of a Porsche and with all the trimming such as electric windows and sun-roofs, the RX-7 was sought by young and old alike. Over 475,000 cars were sold with the original Mark 1 design.
The RX-7 was loved by good and bad alike and appeared in many TV shows, commercials and films.
In Japan the car was adopted by the original Tokyo Drifters and street racers due to its speed and handling. In the UK a modified Turbo version of the 12A RX-7 built by Elford engineering held the unofficial record for the fastest night-time lap of the circular M25 motorway that rings London, for 5 years.
This turbo configuration which used the venturi principle to recycle exhaust gases for extra boost, powered the car to speeds of over 145 mph and was adopted by Mazda into new 13B engine which powered the top end Series 3 production model in Japan from 1984 to 1985.
Various modified versions of the RX-7 were manufactured for different markets around the world, with restricted output and emissions control system in US versions and various bespoke injection and design changes for the European and domestic Japanese Market.
Production of the Mazda RX-7 13B continued until 1988 with the convertible RX-7 Savannah and the new look Mark 2 model often referred to as the Series 4, which had despatched some of the Mark 1 classic design lines and looked more like its main competitor, a Porsche 944.
Dave Healey is a Classic Car Insurance underwriter who is passionate about Mazda RX-7s and modern classic cars. Read more from Dave about the Mazda RX-7 and compare car insurance for all Mazda motors at Car Insurance TV.
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