rx-7 turbo modified

Mazda RX-7 Specs and Details

Mazda is well known for two things: sports cars and the rotary engine. This was mated together in one car: an iconic Mazda RX-7. Out of more than two million rotary engines produced over several decades, over 850.000 of them have been installed in one of three generations of the RX-7. This was a light, simple and agile car that reminded us that spirited driving could still be an affordable treat.

What is a Mazda RX-7 FD?

Back in the 1990s, most Japanese manufacturers were introducing fast sports cars to the market. There was Nissan with a 300ZX, Toyota had an iconic Supra and Mitsubishi just introduced 3000GT. These cars used a similar approach: a powerful six-cylinder engine combined with a various state-of-the-art tech solutions. Mazda, however, took a different approach. In 1992, they released the futuristic looking third generation RX-7, which followed the footprints of its predecessors. Design wise, Mazda RX-7 is a unique car. Smart details like pop-up headlights, a hidden door handles and blacked-out tail lights complemented sleek body lines. Inside the cabin, a driver oriented interior incorporated a minimalistic design approach.

mazda rx7 twin turbo

But what made it stand apart from its rivals was under the hood. This is where one of the rarest and oddest engines lives: a sequential twin-turbo rotary engine. It had twin-turbos that worked together to give smooth acceleration. While the first turbo supplied extra torque at low engine speed, the second set on standby until it reached 4000RPM, where the seamless change-over occurred. This resulted in a screaming and revving, but still a driveable and smooth engine that delivers 255 HP.

twin turbo rotary engine

This engine provides another big advantage because it is light and compact. This allows a traditional front-engine-rear-wheel-drive platform to transform into a mid-engine layout. This improves weight distribution and, combined with sophisticated independent suspension, enables superb handling characteristics. The overall performance was staggering, with superb acceleration, braking and handling. That, combined with the level of driver involvement, made the RX-7 was one of the best sport cars at that time.

What does RX-7 mean?

So far, we have covered the most popular and recognizable of all RX-7 cars, the third generation codenamed FD. This car was a big hit among car enthusiasts because of its virtues. But it was the appearance in movies such as ‘Fast and Furious’ that made it so popular. A red RX-7 with a big ‘VeilSide’ logo on the back that Toretto in the original movie was an instant hit. Still, a modified orange-black car from the Tokyo Drift is the first thing that comes into mind when talking about this car.

rx-7 race car

Still, let’s go back to the beginning. Mazda’s famous for making rotary engine cars this one the original RX-7, codenamed FB. This car got raves in 1978 for its modest price and fun to drive nature. It had a twin rotary 1.2 liter engine that would rev to 7,000 revs. With such a smooth and responsive unit, this car was great fun to drive.

rx-7 first generation

The second generation, codenamed FC, was available as a coupe and a convertible. As it was a bit heavier, the engine grew to 1.3 liters in capacity and had a fuel injection system. This helped increase the power output up to 205 HP in versions with a turbocharger.

rx-7 second generation

When did Mazda stop making the RX-7?

While the final, third generation of the iconic RX-7 was in production up to 2002, it was available as a word-wide model only up to 1995. After that year, the RX-7 was only available in Japan and Australia. In final iterations, the RX-7 received numerous improvements, gaining more power, enhanced aerodynamics, revised gearbox and so on.

racing mazda rx-7

But as production came to a close, Mazda decided that the RX-7 should go out with a bang. So, the last 1.500 cars down the assembly line received special upgrades and a new name. They called it ‘Spirit R’. It was available in Japan only with a series of upgrades ranging from more efficient turbos, better intercoolers and radiators, new lighting design to more comfortable seats and bigger wheels. Being available only in Japan, they were all right hand drives all except for one. Someone high up at Mazda wanted a ‘Spirit R’ for the US, so the company took a left-hand drive model and retrofitted with the ‘Spirit R’ goodies.

Will Mazda bring back the RX-7?

Mazda introduced a successor in 2003, the RX-8. However, for many Mazda fans, the heavier, less sleek and less powerful RX-8 was no substitute for the legendary RX-7. The engine was more fuel efficient and had better emissions ratings, but at the cost of less torque. It also had problems with apex seals, which sometimes led to total engine failure. Even increased fuel efficiency couldn’t save the RX-8 from the economic crash of 2008. The production of this model stopped in 2012.

mazda rx-7 rear

While the RX-7 is no longer in production, it has left a lasting impression in the automotive world and in all of our hearts. Every few years, Mazda teases with news of a new rotary or a new RX-7. Still, it seems that they are not returning their iconic car soon. The only thing left is a hope that one day they will make it efficient enough to pass new emissions standards and still keep the pure fun of the old one.

How the rotary engine works?

Almost all cars today have a traditional reciprocating engine. While coming in various sizes and configurations, they all have cylinders with pistons that move up and down, generating power for the crankshaft. For a normal four-stroke engine to produce power, an engine needs to do four things. It starts with drawing air into the engine, compressing air with a fuel mixture, igniting the air and fuel mixture and finally expelling the burnt air fuel mixture out into the exhaust.

mazda rotary engine

A rotary engine works on the same four-stage basis. However, the way this process is done is very different, as a big rotor does all the work. Examine a single rotor engine, and you will find five main components. There is a front plate, rotor housing, rotor itself and a rear plate. The fifth component is the eccentric shaft, that acts like the crankshaft in a traditional engine. The rotor housing has an intake port, two spark plugs and an exhaust port. While spinning, the rotor creates a vacuum over the intake port and draws air and fuel into the chamber. As the rotor rotates it covers the intake port, and the compression takes place. Two spark plugs fire, forcing the rotor round further until it reaches the exhaust port to expel the burnt air & fuel mixture.

Rotary engine benefits include high power output, extreme compactness, design simplicity with fewer moving parts. Still, there are some downsides. Firstly, rotary engines have a high oil consumption, as the oil is injected into the rotor housing to keep the seals lubricated and chambers separated. Secondly, there are problems with apex seals, which seal the edges of the rotor against the rotor housing. They are prone to pitting or cracking, resulting in causing low compression, a misfire and a bad idle. Lastly, there is an issue of poor fuel economy, as a part of the air & fuel mixture will not get burnt.

Find a Mazda RX-7 repair manual here today.

 

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