1979→1980 Mazda RX-7 GTU
In 1979, shortly after the RX-7 was launched in America, two racing versions with the 12A engine were entered for the Daytona 24-hour race. They qualified first and second in the GTU class, and 32nd and 34th overall. The grid was dominated by cars with large displacement engines, such as the Porsche 935, and the grueling 24-hour race started amid fears that the compact RX-7s would be overwhelmed. In fact, the RX-7s were able to showcase their fantastic handling through the course’s many tight corners, and steadily worked their way up through the field. After a superb performance, the two cars crossed the finish line together, earning a one-two in the GTU class and fifth and sixth overall. This was a fantastic achievement for a first-time entrant, and it was a big surprise for the IMSA.
Our feature car is a development mule for the GTU cars and it was one of the very first RX-7 race cars. It was photographed at the 2010 Rolex Monterey Motorsports Reunion.
In Detail
| tags | SA22C, rx7 |
| submitted by | Richard Owen |
| type | Racing Car |
| production years | 1979 – 1980 |
| built at | Japan |
| production | 2 |
| engine | 2-Rotor Wankel |
| displacement | 1146 cc / 69.9 in³ |
| bore | 70 mm / 2.76 in |
| compression | 9.4:1 |
| power | 74.6 kw / 100.0 bhp @ 6000 rpm |
| specific output | 87.26 bhp per litre |
| bhp/weight | 91.07 bhp per tonne |
| torque | 142.4 nm / 105.0 ft lbs @ 4000 rpm |
| body / frame | Unit Steel |
| driven wheels | Front Engine / RWD |
| front tires | 185/70HR-13 |
| rear tires | 185/70HR-13 |
| front brakes | F Vented Discs / R Finned Drums, Vacuum Assisted |
| front wheels | F 33.0 x 14.0 cm / 13.0 x 5.5 in |
| rear wheels | R 33.0 x 14.0 cm / 13.0 x 5.5 in |
| steering | Recirculating Ball |
| curb weight | 1098 kg / 2420 lbs |
| wheelbase | 2421 mm / 95.3 in |
| front track | 1420 mm / 55.9 in |
| rear track | 1400 mm / 55.1 in |
| length | 4285 mm / 168.7 in |
| width | 1674 mm / 65.9 in |
| height | 1260 mm / 49.6 in |
| transmission | 5-Speed Manual |
| gear ratios | 3.67:1, 2.22:1, 1.43:1, 1.00:1, 0.83:1 |
| final drive | 3.91:1 |
| top speed | ~196.3 kph / 122.0 mph |
| 0 – 60 mph | ~9.2 seconds |
| 0 – 100 mph | ~27.8 seconds |
| 0 – 1/4 mile | ~17.0 seconds |
