Launched in America in March 1971, the Mazda RX-2 was larger, more powerful, and to some eyes, better styled than the R100, with which it would share the showroom. For a size comparison, the R100's piston-engined counterpart was powered by a 4-banger of 1000cc or 1200cc displacement while the RX-2's piston companion, sold as the 616, was powered by a 1586cc engine. Overall vehicle size was comparable to other Japanese makes of the era for each displacement.
Sold as a sedan or two-door pillared coupe versions, the RX-2 debuted what would be come the biggest selling rotary engine, the 12A series. Although an experimental engine circa 1966 had achieved the same 573cc displacement per chamber as the production 12A engine by using the 10A's chamber width and different trochoidal dimensions, the production 12A simply widened the 10A's chamber by 10mm (from 60mm to 70mm). It was effectively the rotary equivalent of a "bore-job." The 12A would power the RX-2 and RX-3 as well as the 1st generation RX-7 and, in Japan, the second series 929 and the 1st generation RX-7 Turbo I.

The 12A debuted in the RX-2, Capella RE in Japan in May 1970. This was the same car that would later come to the US, except for detail changes and elaborate emission controls that centered around the thermal reactor and air pump, as on the R100. The RX-2 added another twist to the R100's reactor, however, by encasing it in metal shell. A portion of the air from the air pump was directed to this cavity and out through a small secondary "tailpipe' that exited next to the real exhaust pipe. From be hind, the RX-2 looked like it had a rather peculiar dual exhaust: two pipes of different diameter! However, it was effective in reducing under-hood heat to mere blast furnace levels. The engine retained the 4-barrel carburetor and side intake/peripheral exhaust ports. To limit exhaust noise, an insert was placed in the exhaust port that divided it into three sections. Though the unrestricted Capella RE was rated at 130bhp at 7000rpm, the thermal reactor brought output down to 120hp at 6800rpm. For the 1972 model year, output was listed as 102hp (perhaps nobody would notice the transposed digits?), and in 1973 the power was listed as 97hp. 
The RX-2 itself featured the "shrunken American" school of Japanese automotive design, looking like nothing so much as a downscaled GM product of the late sixties, especially in the C-pillar area. There was also the Japanese tendency for over ornamentation: "surface excitement" was the name for it, which was the reason the grille had not only a central chrome "tooth" but two badges on either side as well. The RX-2 was considered sporty and therefore came with styled steel wheels with trim rings, even if only 13x4.5" and mounted with 165-13 radials. At least this was better than the home-market model, which came with mere 155-13 tires. Tested with the smaller tire, the RX-2's cornering power was skidpad tested at 0.631G, a disappointment even in 1971.

As on the R100, the RX-2's front suspension was by MacPherson strut, and it had a live axle at the rear as well. The axle, however, was on coil springs and located by four trailing links and a Panhard rod. Road & Track called it "quite adequate," but too soft for some, though "a maneuverable car that can be driven briskly without awkwardness, It's just no racer." The disc/drum brakes were "much more impressive." Good deceleration, good control, no fade, and no squeal. Racers, however, would find the brakes inadequate on the track, one saying he kept them from fading "by not using them."
The interior was praised by Road & Track, which liked the full instrumentation. Gauges included a 135mph speedometer, 8000rpm tachometer, a combination ammeter, coolant temperature, and fuel-level pod, plus warning lights. A console was a small car novelty at the time, small usually being a synonym for cheap. The shifter, which angled hack in an almost Alfa-like manner, was mounted in the console with a soft boot,
The front seats were found to be "reasonably good, not luxurious," and testers liked the adjustable seatbacks but not that they had to be reset after letting a passenger out of the back seat of the coupe (This was rectified before the end of the model run). Amenities included a clock, heated rear window, locking gas cap, and a portable trouble light in the glove box, all standard. There was even a floor courtesy light for the back seat. The magazine deemed the coupe's back seat suitable only for those under 5'8" tall, thanks to the sloping roofline.

(Photo 3)The RX-2 lost trim and badging by 1974, but federal bumper laws required the addition of massive chrome rams on coupe and sedan. Mazda; Automobile Quarterly Photo and Research

A four-speed manual transmission was all that was offered at first, and Road & Track called it "very notchy" with the second and third-gear synchros beatable by a fast shift. An automatic transmission option was added in 1973, a three speed from JATCO (Japanese Automatic Transmission Co., a Nissan/Ford/Toyo Kogyo joint venture). The torque converter had an unusually stall speed of 2450rpm to compensate for the rotary's archetypical lack of low speed torque, but testers liked the part-throttle kick down and smooth shifts in ordinary traffic. Though there were losses in fuel economy (16.0mpg vs 18.0mpg) and performance (18.8sec vs 18.0sec in the quarter mile), Road & Track concluded that "the automatic for the rotary engined Mazda makes sense."
There were a couple of peculiarities with the automatic, however. One was a red light on the dash that came on when the throttle was wide open and the thermal reactor's air pump was shut off, as it was supposed to be during full power.
The United States sales arm was not able to explain why the light was provided. The transmission was also held in a lower gear by the use of the manual choke. For example, if the choke was in use, the transmission did not shift into second until it would normally shift into third. This kept revs up and emissions down during cold-start conditions. Fuel economy wasn't a concern yet.

Problems with oil-seal failure on early (1970-73) 10A and 12A engines required engine overhauls or replacements on rotary-engined Mazdas. Lawsuits initiated m 1975 and 1976 resulted in a 1980 out-of-court settlement in which Mazda denied faulty design, though the company set aside $2.5 million to settle claims. An owners' survey by Road & Track gave preliminary confirmation that the problem bad been corrected. 
Beginning with the 1974 model year, a new process called SIP (Sheet-metal Insert Process) was used on Mazda rotary engines to strengthen the trochoidal surface and enhance productivity, A sheet metal insert with a rough outer surface was east into the aluminum-alloy rotor housing and then hard chrome plated. Chrome plating adheres better to sheet metal, and the process eliminated the spraying of the trochoid surface with molten metal, a procedure that has been called dangerous and unpleasant. Another change, made possible by SIP and pinpoint-porous chrome plating, was the switch from carbon compound rotor tip seals to cast iron, similar to ordinary piston-ring material. Horsepower "decreased" in 1972, thanks to the federally mandated use of SAE net instead of SAE gross power rating.
(Picture 4) Note the trim difference on this 1974 RX-2; new "power bulges" on hood are evident.
The RX-2 was dropped from the Mazda line at the end of the 1974 model year, since it seemed redundant with the addition of the longer, lower, wider, and faster RX-4 as the sportiest Mazda in America.

What to Look For The RX-2 was imported in greater numbers than its predecessors, so the likelihood of survivors is greater. On the other hand, some became racers, which works for and against their survival. And in some cases, those that endured the rigors of competition may be now greatly distressed. A racer won't make a good candidate for restoration to original condition, as the interior will be gutted (although racers may have original parts for your road-car restoration stashed in a corner somewhere) and the exterior modified, rather by or accident On the other hand, an old racer would be a good vintage race candidate, although many of them are still actively being raced in SCCA competition, both in GT and IT classes, It's probably better to restore a racer as a racer and keep that part of its history intact. All in all, a stock RX-2 is rare. Says one RX-2 racer, "They've all been gobbled up for road racing"
If you are lucky enough to have a choice of original RX-2s, the better bet would be the later year, with 1974 the best because of the engine improvements. On the other hand, it would probably be better to buy the car in better overall condition. Or buy them both. They're cheap.
As with the earlier cars, interior parts and exterior trim, windshields, and other specific parts will be very hard to find. though less so than for the R100 or 1800. No reproduction body parts are available either. The 12A engine, however, can be rebuilt, or replaced with a later 12A if necessary. Owners should check electrical systems; connectors can corrode and the resulting resistance could start a fire in the electrical system.
(Picture 6) Perhaps the most famous racing RX-2 was the Car & Driver car, later campaigned by Wait Bohren and ethers Mazda

Though the engine may need to be rebuilt, depending on the car's history, the rest of the drive train will probably be solid Transmission synchronizers tend to be weak, but the gears, bearings, and such have the reputation of being "tough as nails."
The RX-2 is stout. Almost every Mazda rotary sedan fan has a story of the RX-2 or other Mazda sedan holding up well in a collision Paradoxically, the sheet metal on the early sedans seems thin and more prone to rust and rust-through than the con- temporary American car.
As Mazda's first really successful model, the RX-2 carries some historical significance, though demand isn't overwhelming for the model. As with the RICO, costs for any significant restoration will still probably exceed market value. Look for a good one.