Mazda RX-7 FB, The Complete Buying Guide

Overview

The first-generation Mazda RX-7 (known as the FB or SA/FB22) was the car that proved a rotary engine belonged in a proper sports car. Launched in 1978, the FB was Mazda’s response to the Porsche 924, and at roughly half the price, it was a stunning bargain. Light, balanced, and powered by the proven 12A and later 13B rotary engines, the FB delivered a driving experience that embarrassed cars costing twice as much.

For the Australian buyer in 2026, the FB RX-7 represents the most affordable entry point into rotary sports car ownership. Clean examples range from $15,000-25,000 AUD, a fraction of the cost of an RX-3 or FD RX-7. The FB is also the simplest RX-7 generation to maintain: no turbocharging, no complex electronics, and a huge community of knowledgeable owners who have documented every aspect of ownership.

The FB was produced in three series. Series 1 (1979-1980) and Series 2 (1980-1983) used the 12A rotary engine producing approximately 100hp. The Series 3 (1983-1985) received the larger 13B rotary engine producing approximately 135hp. The Series 3 with the 13B is the one most buyers should target, it offers notably more torque, better durability, and the engine responds well to modification.

This guide covers what to look for, the critical rotary-specific inspection points, and the real costs of ownership.

What to Look For

Engine, The Rotary Heart

12A Engine (Series 1 and 2):

• The 12A is a 1,146cc twin-rotor producing approximately 100hp (74kW). It’s the same basic engine found in the RX-3, further developed for the RX-7 application. The 12A is smooth and willing to rev, but it lacks the low-end torque that makes the 13B more enjoyable for road driving.
• The 12A is more fragile than the 13B. It doesn’t tolerate sustained high-RPM use as well, and apex seal life is generally shorter.
• Parts availability for the 12A is good but not as extensive as the 13B.
• If buying a 12A car, budget for the eventual swap to a 13B. Many owners do this conversion and it dramatically improves the car.

13B Engine (Series 3):

• The 13B is a 1,308cc twin-rotor producing approximately 135hp (100kW). The additional displacement over the 12A translates to meaningfully more torque, making the car more relaxed in everyday driving while still revving freely to its 7,000+ rpm limit.
• The 13B is the more robust engine. Apex seal life is better, the bottom end is stronger, and the larger displacement gives more headroom for modifications.
• The 13B in the FB is naturally aspirated with a Nikki 4-barrel carburettor. It’s a simple, well-understood engine configuration.

Compression Test, MANDATORY: Do not purchase any FB RX-7 without performing a warm compression test. The procedure is the same as for any twin-rotor Wankel:

• Warm the engine to full operating temperature.
• Remove all spark plugs (four on a twin-rotor, two per rotor, leading and trailing).
• Install the compression tester in one plug hole, crank with throttle wide open.
• Record readings for all three faces per rotor (six total readings on a twin-rotor).
• Healthy 12A: 100-120 psi, less than 10 psi variation.
• Healthy 13B: 110-130 psi, less than 10 psi variation.
• Below 85 psi on any face or more than 15 psi variation: walk away or budget for a rebuild ($2,500-4,000).

The Oil Metering Pump: The FB uses a mechanical oil metering pump (OMP) to lubricate the apex seals. On a 40+ year old car, the OMP is a critical concern. Many experienced owners supplement the OMP with fuel pre-mixing (two-stroke oil at 1:200 ratio) or delete the OMP entirely and rely on pre-mix alone. If the OMP has been deleted, verify that the previous owner was disciplined about pre-mixing, a dry rotary dies fast.

Cooling System: The FB’s cooling system is adequate for normal driving but marginal for spirited use or hot Australian conditions. The rotary engine is extremely sensitive to overheating, a single event can warp the rotor housings and destroy the engine.

• Check the radiator for leaks, corrosion, and reduced cooling capacity. An aftermarket aluminium radiator ($300-500) is a recommended upgrade.
• Check all hoses, rubber perishes with age.
• Verify the thermostat opens at the correct temperature.
• Check the electric cooling fans for operation. A failed fan in traffic will overheat the engine rapidly.

Rust, The Body Issue

The FB RX-7 is prone to rust in specific areas. Australian cars are generally better than northern hemisphere examples, but 40+ years of exposure takes a toll.

Critical rust areas:

• Rear quarters behind the wheels: This is the FB’s worst rust area. Water gets trapped inside the quarter panels and corrodes from the inside out. Look for bubbling paint, filler, or soft metal behind the rear wheel arches. Repair panels are available but the work is expensive.
• Hatch/tailgate area: The hatch surround and the lower edge of the hatchback corrode. Check the seal areas and the lower lip of the hatch opening.
• Front inner guards: Mud and debris accumulate against the inner guards. Poke for soft metal and check from above and below.
• Sills: The box-section sills trap moisture. Inspect from underneath, corroded sills are a structural issue.
• Battery tray: Acid vapour corrodes the tray and the surrounding structure.

Body panel availability: FB body panels are more available than RX-3 panels but still not plentiful. Aftermarket reproduction panels exist for common rust areas (rear quarters, sills). Used panels from wreckers are increasingly scarce as the FB population diminishes. Budget $500-2,000 per area for professional rust repair.

Suspension

The FB’s suspension is simple and effective: MacPherson struts front, live rear axle with a Watts linkage (a sophisticated setup for a live axle that minimises lateral movement).

• Check for leaking shock absorbers, the originals are well past their service life. Budget for a complete set of quality replacements (Bilstein, KYB). Cost: $400-800.
• Front strut top mounts wear and cause clunking. Cost: $50-100 per side.
• Rear control arm bushings perish. Cost: $100-200 per side.
• The Watts linkage bushings and pivot wear, causing lateral movement of the rear axle. This is felt as vagueness under hard cornering.

Gearbox

The FB uses a 5-speed manual (most desirable) or a 3-speed automatic. The 5-speed is a reasonably robust unit that handles stock power without issues. Check for:

• Synchro wear, grinding when shifting into 2nd or 3rd indicates worn synchros.
• Gearbox whine, worn bearings.
• Difficulty engaging reverse, common and usually a linkage adjustment rather than internal damage.

Electrical

The FB’s electrical system is straightforward but age-related issues are common:

• Pop-up headlight motors can fail. Replacement motors are available but the mechanism needs periodic lubrication.
• Dashboard warning lights and gauges may have intermittent connections.
• Aftermarket ignition systems (replacing the factory points or early electronic systems) are a common and desirable modification.

Price Guide (Australia, 2026)

Series 1 (12A, 1979-1980)

• Project (needs mechanical and body work): $3,000-6,000
• Driver (runs, cosmetic issues): $6,000-10,000
• Good (sorted, presentable): $10,000-16,000

Series 2 (12A, 1980-1983)

• Project: $3,000-7,000
• Driver: $7,000-12,000
• Good: $12,000-18,000

Series 3 (13B, 1983-1985)

• Project: $5,000-8,000
• Driver: $8,000-15,000
• Good (clean, healthy engine): $15,000-25,000
• Excellent (low km, original): $25,000-35,000

The Series 3 commands a significant premium due to the 13B engine. Manual models are worth 15-20% more than automatics.

Running Costs

Fuel: Expect 13-16 L/100km in mixed driving. Use 98 RON premium unleaded. The rotary’s fuel appetite is a known trade-off, accept it as part of ownership. Pre-mix two-stroke oil adds a minor additional cost.

Oil: Change every 5,000 km using 20W-50 mineral or a quality rotary-specific oil. Oil capacity is approximately 4.0-4.5L. Check the level regularly, the rotary consumes oil by design.

Parts: Mechanical parts (engine seals, gaskets, suspension components, brake parts) are well-supplied through rotary specialists and general parts retailers. Body and trim parts are becoming scarce. The FB shares many components with later RX-7s, which helps availability.

Insurance: Agreed-value classic car policy recommended. Budget $500-1,000/year depending on agreed value.

Annual maintenance budget: For a well-sorted FB in regular use: $1,500-3,000/year. This covers oil changes, minor repairs, and one unexpected issue.

Which Variant?

Series 3 with 13B engine is the clear recommendation. The 13B is the better engine in every respect, more torque, better durability, and superior parts availability. The Series 3 also benefited from incremental improvements to the chassis and interior.

Manual transmission is essential for the full experience. The 3-speed auto is adequate but robs the car of its sporting character.

Limited Edition and GSL-SE variants (if available in Australia) command premiums for their additional equipment and factory sport suspension.

The Verdict

The FB RX-7 is the accessible rotary sports car. It delivers the unique rotary experience, the smooth power delivery, the willingness to rev, the mechanical simplicity, in a properly designed sports car platform at a price that won’t bankrupt you. The FB is light (around 1,050kg), balanced, and engages the driver in a way that modern cars simply cannot.

Buy the best Series 3 you can find. Get a compression test. Check the body for rust behind the rear wheels. Budget for cooling system and suspension upgrades as immediate priorities. And pre-mix your fuel, the engine will thank you for it.

The FB may not have the visual drama of the FD or the cult status of the RX-3, but it’s arguably the purest expression of Mazda’s rotary sports car philosophy: light weight, mechanical simplicity, and driving involvement above all else.