Sometimes you see a car and you know immediately that it’s going to be something amazing. It’s interesting to note that many of these legendary works originated in a certain era. Japan in the 1990s is the time period under consideration here. In that era, Japanese automakers understood the importance of producing high-performance vehicles that could be purchased by the average person without breaking the bank.
Although Nissan, Mitsubishi, and Subaru were all producing timeless automobiles, Mazda and Toyota were head and shoulders above the competition. The RX-7 nameplate had been in use for over 15 years by the time the 1990s rolled around. The Supra is no different in this regard. When first conceived, the two were very dissimilar. The RX-7 was designed with entertainment in mind from the get-go, while the Supra was a wedge-shaped grand tourer. As time went on, the Supra caught up to the RX-7 in terms of sporting enthusiasm.
In 1993, with the debut of the FD RX-7 and MkIV Supra, competition between the RX-7 and Supra reached a fever pitch. Both were well-honed machines by that point, offering comparable functionality for around the same cost. They were a great pairing on paper, but they did the work that got them noticed in quite different ways.
RX-7 vs Supra – Mazda RX-7 History
Mazda has used a variety of approaches over three models of the RX-7 during the length of the car’s 24-year production run. No doubt many pages could be devoted to detailing the RX-7’s history, but for the sake of brevity and overview, that’s all we’ll do here.
In 1978, Mazda introduced the SA22C chassis, the forerunner to the current-generation RX-7. For the RX-7, Mazda had a very specific vision: to create a sports car that was both economical and accessible to a wide range of buyers. They actually did that! The Mazda SA was the company’s second vehicle to offer a Wankel rotary engine. Though it only makes 100 hp, the 1.1L 12A rotary that drives the SA is a real hoot. The SA pioneered the combination of high-rev performance and a lightweight chassis.
In 1981 came the FB, which was essentially a SA with some major upgrades. While the FB was initially seen as being just slightly superior to the SA, the gap between the two had grown significantly by 1985 thanks to the modifications. The SA and FB differ mostly in their outward appearance, although the FB also features an improved 5-speed manual transmission and an engine upgrade that increases output by 10 horsepower. In 1984, a more substantial engine change occurred, swapping out the 1.1L 12A rotary for a 1.3L 13B RE-EGI rotary that produced 135 hp.
After the original RX-7’s release in 1983, the FC generation RX-7 arrived in 1986. While the SA and FB generations made great strides in weight loss, the FC gave up trying to cut calories altogether. Because of this, the FC was far more cumbersome than its forebears. To make up for it, Mazda installed an upgraded version of the 13B engine used in the FB, increasing its output to 145 hp. The FC’s good performance was expected given its target market of sport-tourers thanks to its independent rear suspension, precise steering, and tuned handling characteristics. There was also a version with a twin-scroll turbocharger that boosted power to 180 hp.
The third iteration of the RX-7, and the one most people are familiar with, debuted in 1992 under the FD chassis designation. The FD marked a return to the RX-7’s roots as compared to the FC generation that came before it. The FD resumed the diet the SA and FB had been following and lost a lot more weight than the FC. More impressively, the 13B-REW was powered by Mazda’s most potent production rotary at the time. The REW upped the FD’s power to 252 hp and was the first mass-produced sequential twin-turbocharged engine exported from Japan. A bit of a nuisance to drive due to its unusual engine configuration.
Toyota Supra History
The Supra nameplate, like the RX-7 nameplate, has a long and storied past, and it has evolved in various ways throughout the years. As with the RX-7, manufacture of the first four generations of the Supra ran from 1978 to 2002. Prior to 1986, the Supra was inseparable from Toyota’s Celica lineup to the point where both names were used interchangeably. An inline-6 engine format has always been a feature of the Supra range, going from the first generation all the way to the present 5th generation.
Most of the body panels, beginning with the doors, on the first generation A40 Supra were carried over from the Celica. Front fenders were stretched to accommodate the larger inline-6 M-EU, 4M-E, and 5M-E powerplants. The first-generation Supra wasn’t built for speed due to its high curb weight and low power output. Its style and personality were intended to reflect that of a grand tourer. Power for the A40 Supra was bumped up to 116 from 86 with the 1980 installation of the 2.8L 5M-E engine.
As its name suggests, the second-generation A60 Celica Supra was built on a modified version of the Celica’s chassis. The A60’s more angular and aggressive design indicated a slightly more directed focus on performance, while it was still classified as a grand-tourer due to the inclusion of rear seats. The 145-horsepower 5M-E inline-6 remained standard on international models until 1983, when it was upgraded to 150 hp and again in 1984, when it reached 160 hp. Toyota took the message that consumers valued athletic features above opulent ones between 1981 and 1986, and the A60 evolved accordingly.
Separating itself completely from the Celica brand, the third-generation A70 Supra finally found its own character. In the late 1980s, integrated technology was all the rage, much like the second-generation FC RX-7. Because of this, the A70 weighed a lot. As a consolation, Toyota included a powerful 3.0L inline-6 engine that generated 200 horsepower in the base model. In 1987, a turbocharged A70 with the now-iconic 7M-GTE engine was released, boosting power to 231 hp.
The fourth-generation A80 Supra, often known as the Mk4, debuted in 1993 with a major redesign that prioritized performance. Engineers made significant changes to reduce weight, and the Mk4’s chassis is perfectly balanced as a result. The Mk4 also features an upgraded engine. Certainly one of the most well-known propulsion systems ever created. The 6 cylinder 2JZ, which superseded the 7M, came in naturally aspirated and sequential twin turbo configurations.
RX-7 vs Supra – Engine
Powertrains are a selling point for both the FD RX-7 and MK4 Supra. Well-known for its 1.3-liter 13B-REW rotary engine, the RX-7 has quickly become a fan favorite. The 2JZ-GTE inline-6 engine is what gives the Supra its legendary performance. Undoubtedly legendary, both cars and engines are infamous for different reasons. Because of their fundamentally distinct modes of operation, it is difficult to draw direct comparisons between rotary and conventional inline-6 engines in terms of raw technical specifications. We’re going to give it a shot, though. The engine specifications of the RX-7 and the Supra are discussed here.
Mazda RX-7 13B-REW Engine
If Mazda is known for one thing, it would be their implementation of the rotary engine in many of their cars. Mazda’s first rotary-powered car was the Cosmo, which was released in 1967. So, they clearly have a handle on the rotary formula. The rotary, or Wankel, engine defined Mazda for decades, as it provided a different experience and new engine characteristics to the world market. The 13B-REW is the pinnacle of Mazda’s road-going rotary lineup and became one of the most famous examples of the Wankel format due to its placement in the FD RX-7. Here are the specs of the 13B-REW:
|Engine||Mazda 13B-REW Engine|
|Displacement||1.3L (1,308 cc)|
|Bore x Stroke||N/A|
|Torque (lb-ft)||217 lb-ft|
How Does a Rotary Engine Work?
If you’re unfamiliar with rotary engines, let’s just say that everything you know about conventional piston engines goes out the window. A rotary engine, in the most basic terms, is an alternative to a piston engine that uses the same basic formula for combustion and emission. Combustion pressure in a rotary engine is confined within a chamber generated in the gap between the engine’s casing and internal triangle rotor, as opposed to conventional piston engines, which use the pressure within the cylinders to force a piston back and forth.
In the same way as a regular engine, fuel and air are fed into the combustion chamber. Next, the mixture is ignited using two spark plugs within the combustion chamber. Triangular rotor inside engine housing is rotated by combustion process. Each of the rotor’s three vertices is in constant contact with the engine housing, and all three chambers on the triangular rotor’s sides perform a specific function. While the rotor is in motion, air and fuel are pumped into one of the three chambers. At this point, it is turned to face the engine’s ignition system, where combustion really takes place. The rotor then spins, allowing the gases to escape.
The seals at the rotary engine’s rotor’s apexes where it contacts the engine housing are a major design flaw. The engine housing can be damaged if the sharp apex seals are not properly greased. The engine’s compression will eventually suffer as a result of this. The fundamental flaw of the 13B-REW is the apex seal’s tendency to fail. Check out our guide to the 5 Most Frequent Mazda 13B-REW Engine Issues if you want to know more about the various issues that might arise with this model of Mazda’s engine.
What’s So Great About Rotary Engines?
That certainly wasn’t a detailed explanation of how a rotary works, but it should have given you some notion. The rotary engine in the FD RX-7 may have you wondering why Mazda is so fond of the design. I see your point. Despite its unconventional design and occasional idiosyncrasies, the Wankel engine is a powerful and reliable machine.
However, as compared to a conventional piston engine, the overall design of a rotary engine is rather straightforward. The typical conventional engine, in comparison to a rotary, has many more moving parts. Pistons, rods, valves, springs, rockers, belts, gears, and crankshafts are all absent in a rotary engine. The most important of these is the reduction in weight, but there are others as well. When compared to its piston-based equivalents, rotary engines can save considerable weight due to their reduced number of moving parts.
In many respects, rotary engines are more refined than their piston counterparts. The primary driving components of a rotary have less vibration since they are counterbalanced and run in a smooth cyclical motion. Additionally, their power supply is more consistent.
Compared to other engine types, rotary engines are far more economical with fuel and can generate substantial amounts of force with relatively small inputs. Specifically, the 13B generates 178 hp/liter. That means the 13B-REW, in its factory configuration, can generate 252 hp despite having a relatively small 1.3 L displacement. Such economy is usually only found in high-performance supercars, making its appearance in a vehicle that initially cost a third of the price of cars achieving similar results all the more astonishing.
Toyota 2JZ-GTE Engine
The 2JZ-GTE engine from Toyota is renowned, and almost every auto enthusiast has at least heard of it. When Toyota introduced the 2JZ in 1991, it was already a very unusual engine in its basic state. The 3.0 liter DOHC twin-turbo inline-six engine produces 320 hp as-is. It’s not quite as cutting-edge as the 13B-REW, but it’s still one of the finest examples of the age-old design of the piston engine. Specifications for the MK4 Supra’s 2JZ-GTE motor are as follows:
|Engine||Toyota 2JZ-GTE Engine|
|Displacement||3.0L (2,997 cc)|
|Bore x Stroke||86mm x 86mm|
|Torque (lb-ft)||315 lb-ft|
What Makes the 2JZ-GTE Such A Good Engine?
The 2JZ-GTE is able to tolerate high boost thanks to its low compression ratio of 8.5:1. The square-cylinder layout strikes an excellent blend between low-end oomph and high-speed prowess. The 2JZ is Toyota’s super-sturdy, iron-block, closed-deck engine design. Even though they weren’t forged, the cast pistons’ strength and heft are unmatched. For piston cooling, they had oil spray nozzles. After that, we have the forged crank and connecting rods.
What I want to say is that the Toyota 2JZ is unmistakably constructed to last. You’d want to see almost exactly those numbers on a high-performance motor. The 2JZ gained widespread recognition for its adaptability to many aftermarket modifications. Since it can withstand significant amounts of punishment, the 2JZ-GTE is one of the most sought-after engines in the aftermarket. This directly translates into some insane Mk4 Supra builds, with power levels frequently falling into the four-digit range.
As a result of Toyota’s overengineering, a 2JZ-GTE is a highly dependable motor whether you tune it or not. The 2JZ has few glaring flaws, and even fewer can cause serious engine damage. The 2JZ-GTE is legendary because of all of the aforementioned reasons. The outcome was that the Supra became a legend in its own right.
RX-7 vs Supra – Performance
Now that we’ve discussed the power plants that run these two monsters, let’s compare and contrast how they are to operate behind the wheel. Despite being lumped together in the same category whenever performance is discussed, there is a substantial gap between the two in terms of how they drive under pressure. The performance comparison between the RX-7 and the Supra is laid out below.
RX-7 vs Supra – MK4 Supra Performance
The MK4 is undeniably more performance-focused than its forebears, but it still has a good amount of GT DNA. As the MK4 Supra’s curb weight makes very clear. The 2JZ-GE-powered MK4 weights between 3,100 and 3,300 pounds without the turbocharger, and between 3,300 and 3,500 pounds with it.
As a result of these factors, it should come as no surprise that the MK4 Supra isn’t exactly a featherweight. The basic suspension on the Supra is also not particularly impressive. The Supra’s hefty curb weight and sloppy suspension gave the impression that it was more suited for the open road than for the circuit. A MK4 may be thrashed through corners with ease if you equip it with rear sticky tires. After the debut of the MK4, its exceptional cornering grip was hailed as a major improvement. The power is sent to the rear wheels, thus it’s important to be cautious when applying throttle.
Adding in some performance upgrades makes the Supra come to life. We’ve already established that the standard Supra suspension isn’t up to pace with what’s available nowadays. A MK4 may be made into a considerably more capable car with the addition of a good set of coilovers and some chassis strengthening adjustments. There is no shortage of 2JZ-GTE upgrades if you’re after increased output and top speed. We have a comprehensive guide to the Toyota 2JZ-GTE engine if you’re interested in tuning a Supra with one.
RX-7 vs Supra – FD RX-7 Performance
The FD RX-7, in contrast to the MK4 Supra, was designed from the ground up to be a dedicated sports vehicle. That’s because it comes equipped with all the necessary components already. The RX-7 is noticeably lighter than the MK4. The FD is about 400 pounds lighter than the lightest MK4 and a stunning 600 pounds lighter than the turbo. The RX-7’s superior handling in stock form compared to the Mk4’s is mostly attributable to the difference in weight.
The RX-7 also features a more sporty suspension geometry, a better connection to the road, and a penchant for high rpm. True, that is one of the FD’s most distinctive features. With a redline of 8,000 rpm, Mazda anticipates that you will always be revving the engine to its limit. The RX-7’s sweet spot for power is between 6,000 and 7,500 rpm, so you’ll need to rev it to the limit to get the most out of it.
Interesting performance traits can be attributed to the FD’s cutting-edge Hitachi sequential turbo system. At 1,800 rpm, one turbo takes over for the other until the second turbo kicks in at 4,000 rpm. Because of the sudden increase in power when the second turbocharger kicks in, drivers must adjust their driving technique at the turbo changeover point. The MK4’s sequential turbo arrangement is almost comparable, with one turbo providing boost at 1,800 rpm and the other coming into play at 4,000 rpm. The power band is less choppy in the MK4 because exhaust gas is fed into the secondary turbo in advance of the changeover point.
RX-7 vs Supra Conclusion
Although many people group the FD RX-7 and MK4 Supra together, they were actually designed for separate goals. Throughout its 24-year production run, the RX-7 served a specific purpose in Mazda’s lineup: that of a lightweight, exotic, and speedy roadster. Having a rotary engine made it one of the most unusual sports vehicles available at the time, and it still has that distinction today.
Contrarily, the Supra has always been a grand tourer before it was even considered a sports car. From the Supra’s first three versions, it’s obvious that Toyota envisioned a position for the car that was more autobahn-focused than Nurburgring-focused. But that doesn’t mean the MK4 Supra isn’t a competent sports vehicle. Its cornering ability and sheer power are two of the MK4’s many lauded features. The Supra’s factory suspension is its weakest link when it comes to handling performance. The body roll of a Supra can be reduced with a few tweaks, such as new suspension and sway bars.
The choice between an FD RX-7 and a Supra ultimately comes down to your performance needs. If you want a unique sports car that can do some serious damage on the track, a stock RX-7 is your best chance. The RX-7 is a fantastic car to drive, but it isn’t very reliable and requires a lot of pricey repairs. Instead, the Supra is an excellent pick for a speedy cruiser. If one takes the time and invests the resources, a Supra can be made to spec. MK4 Supras may not be as quick off the line in their factory configuration, but they are highly reliable and extremely adjustable.