The RX-7 bucked convention for a more adventurous Wankel rotary engine, which gave the sports car up to 252 HP and an exclusive driving experience.
Key Points
- Mazda produced three generations of the RX-7, featuring three different major rotary engines.
- Turbocharged versions of the engines became available in the second and third generations.
- 12A-equipped cars produced 100 horsepower, and 13B-equipped vehicles got 146 to 160 horsepower.
- Turbocharged models saw power increase to 182 to 200 horsepower.
- 13B-REW engines were the first mass-produced sequential twin-turbocharged systems to be exported from Japan.
- The rotary engine hasn’t been in a production vehicle since 2012, but MX30 will have a rotary hybrid option.
1.3L Wankel Rotary Engine Delivered Affordable Exotic Car-like Performance
The Mazda RX-7 debuted in 1978 and remained a popular vehicle for nearly 25 years because of its strategic weight distribution, wide array of modifications, and mostly, its unique rotary engine. When it came to the RX-7, Mazda steered from convention and toward the more adventurous 1.3L Wankel rotary engine.
The Rx-7 was a successor to a long line of rotary-powered Mazdas. Like the Mazda Luce, Cosmo, and RX-3 that came before it, the RX-7 used this simple engine to provide an exclusive driving experience only found within the Mazda brand. The new rotary-powered platform allowed enthusiasts to drive what felt like an exotic car but without breaking the bank.
With competition from the Nissan GTR and Toyota Supra, the Mazda RX-7 had its work cut out for it. Fusing supercar-level handling with a lightweight two-door coupe design made the RX-7 stand out from the start. But what gave the RX-7 its legendary status?
1.2L 12A and 1.3L 13B Engines Made RX-7 a Strong Sports Car Contender
Clearly, the RX-7’s small size and perfect 50/50 weight distribution played a huge part in why it became and remains a beloved sports car. However, the most important factor lies under the hood of the Mazda RX-7.
The fast-revving 1.3-liter two-rotor engine, formally known as the 13B, makes the RX-7 come alive. With a piercing 8,000 rpm redline, the rotary engine sings happily through every gear.
While the first-generation RX-7 engines were offered in a 1.2-liter configuration, known as the 12A, the true hero that keeps the rotary community alive is the 13B. But it is a bit sluggish in lower rpm driving, which means you can enjoy wringing out each gear without the worry of damaging the engine.
Over the years, the Mazda RX-7 has had a few variants of the 13B available. Here, we’ll provide a breakdown of the 12A and 13B rotary engines.
RX-7’s First-gen. 12A Engine Offered 100 HP, Respectable EPA Ratings
The first generation (1978-1985) of the Mazda RX-7 came with the 12A rotary engine under the hood. They were available with a four-speed manual or three-speed automatic transmission. Later year models were offered with five-speed manual or four-speed automatic transmissions.
The 12 in 12A tells you it is a two-rotor engine with a displacement of 1.2 liters. Due to how a rotary engine produces power, it can produce one and a half times more power than a piston engine of the same liter.
Power output stayed relatively the same throughout the years the 12A engine was offered in the RX-7. As a carbureted two-rotor, the 12A produced 100 horsepower and 105 lb.-ft. of torque. The rotary’s biggest advantage is how smooth the combustion cycle is. Being able to rev up to 8,000 rpm with ease made for a smooth power band in every gear.
Fuel economy for the time was respectable, providing EPA ratings of 15 mpg city and 20 mpg highway.
While it was only offered in the Japanese market, late model first-generation RX-7s received a turbocharged version of the 12A. These models were referred to as the Savanna RX-7 Turbo and produced 163 horsepower. However, this turbo model would be short-lived, as the next generation of RX-7 would be announced just after.
Second-gen. Added New 13B Engine, Amped Up Output to 160 HP
For the second generation (1985-1992) of the RX-7, Mazda upgraded the rotary engine platform and the chassis. The new 13B rotary engine would see the addition of electronic fuel injection, better rotor seals, and newly machined housings to increase displacement to 1.3 liters.
These improvements saw a power increase from 100 to 146 horsepower and 105 to 135 lb.-ft. of torque. The naturally aspirated 13B would stay relatively the same until late model (Series 5 as they’re referred to) cars. A late-model 13B would gain power from better engine management, lighter rotors, and a higher compression ratio of 9.7:1. As a result, power increased from 146 horsepower to 160.
After the success of the first-generation turbo engine for the Japanese market, Mazda saw fit to develop a turbo 13B engine for other markets. Thus, during the Chicago Auto Show in 1986, Mazda announced the RX-7 Turbo II. The Turbo II engine would produce 182 horsepower and 183 lb.-ft. of torque at only 3,500 rpm. These turbo models were very sought after, especially by enthusiasts, meaning the ones you find used are more likely to be taken care of.
Third-gen. RX-7 Entered ’90s with 13B-REW Engine with Twin Turbos and 252 HP
The third generation (1992-2002) of the Mazda RX-7 was released in 1992 and was the first model year to have the 13B-REW. Built upon the same platform as the previous generation, the REW now came standard with twin turbos.
Mazda’s 13B-REW was the first-ever mass-produced sequential twin-turbo system to be exported from Japan. The system would use a small turbo to add boost pressure at lower rpm, then switch to a larger turbo to add boost pressure at higher rpm. Although, the engine would use a complicated rubber hose vacuum system which will fail over time.
All of this new technology would prove beneficial for the 13B engine, as power would increase from 182 horsepower in the Turbo II to 252 horsepower in the new FD RX-7. In addition, torque numbers would increase to 218 lb.-ft., largely due to the smaller sequential turbo.
Impressively, even with more power and complicated emissions, the gas mileage of the last generation RX-7 went up. The new engine helped the RX-7 reach EPA ratings of 18 mpg city and 24 mpg highway.
What Years Did Mazda Make the Rotary Engine-powered RX-7?
The 1978 Mazda RX-7 was the first model year to hit North America. However, it was not the first time Mazda offered a rotary-engined vehicle for the U.S. market. Before the RX-7 came the RX-3 in 1971. Again, another two-door sports coupe with a unique engine platform, the RX-3, lacked sales due to the U.S. oil embargo of 1973-1974.
Needing a comeback, Mazda redesigned the sports coupe model to make the RX-7. Along with the style upgrade, Mazda continued to improve upon its famous engine.
The Mazda RX-7 would be available in three different generations, spanning from 1978 to 2002. It was replaced after three generations by the Mazda RX-8 in 2003, which would also be discontinued in 2012.
The RX seemed to be the last rotary-powered car from Mazda until a new hybrid rotary vehicle was announced in 2021: the Mazda MX30, which will also be offered with a fully electric drivetrain.
Is the Mazda RX-7 a Good Car?
The Mazda RX-7 was available from 1978 to 2002, before it was replaced by the relatively short-lived RX-8 in 2003. It was Mazda’s last rotary-powered car until the Mazda MX30, a new hybrid rotary vehicle, was announced in 2021.
Fortunately, to experience Mazda’s rotary engine experience, you don’t have to wait for the MX30 nor shell out a small fortune, because the RX-7’s reputable and reliable engines have made it an affordable option in the used market.
In terms of being the most affordable, the first-generation RX-7s with the 12A engine is the cheapest. Although they don’t pop up as often as some of the other generations, they are usually $5000 or less. These engines are also the most simplistic for a new rotary owner, making them the best to start with.
However, if you have the extra cash and can afford to get a 1992 to 2002 model year, the extra power bump from turbocharging and chassis improvements is definitely worth the investment. Most third-generation Mazda RX-7s can be found around the $30,000 price range. While it may seem like a lot, you get a phenomenal all-around sports coupe with loads of power.
As always, be sure to use our free VIN check tool to check the vehicle’s history properly. Furthermore, if the seller has records or receipts with the RX-7, it will show a properly maintained car. So, whether you get a Mazda RX-7 with the 12A, 13B, or 13B-REW, you are likely to have found a solid, reliable vehicle that has a large enthusiast community to help you along the way.
Photos: Mazda
