74-82 12A & 13B Racing Beat Lightweight Steel Flywheel (11436)
Racing Beat-designed RX-7 flywheels are both engineered and manufactured by Racing Beat for a wide variety of rotary performance applications. This Racing Beat Lightweight Steel Flywheel can be used on any early (pre-RX-7) RX-2, RX-3, RX-4, Cosmo, and Rotary Pick-Up engine as well as all 1979-92 RX-7 12A and 13B non-turbo engines. As designed by Racing Beat, this flywheel is compatible with all 1974-82 215mm Mazda Factory and Racing Beat clutch discs.
Note: As of 2/2012 the Racing Beat Lightweight Steel and Aluminum Flywheel kits include the hardware kits; however, the required rear counterweights are available separately - see below.
Applications: Designed to retain enough mass for comfortable standing starts this Racing Beat flywheel is ideal for street use, yet it is sufficiently lighter to afford a noticeable improvement in low speed acceleration and to make shifting much smoother. For street use our lightweight steel flywheel not only allows the engine to accelerate more rapidly, but it also eliminates much of the rubbery feel that occurs at clutch engagement while shifting.
Precision Machining: Precision CNC-machined from high strength steel, our flywheel assembly is mated to the Mazda OEM ring gear, then surfaced hardened using a ferritic carburizing heat-treating process, creating an extremely durable disc wear surface. The ring gear is thermally-mated to the flywheel and bolted in place for added security to prevent slippage during engagement of the starter motor.
Weight Comparison: The weight of the stock flywheel is 23 lbs., compared to 13 lbs for the Racing Beat Flywheel. The actual reduction in inertia from stock is much greater than the weights suggest, since the stock flywheel is 1 to 2 inches thick at its outside edge.
Retaining Critical Engine Balance: The installation of an aftermarket flywheel requires the use of a Mazda rear counterweight unit to ensure critical balance of the internal rotating assembly (engine rotors). As produced by Mazda, the original stock rotary flywheel features a pronounced balancing mass included in the flywheel casting. This balancing mass, combined with the stock front counterweight unit, provides the correct balance required for the optimal rotational operation of the engine rotors.
To allow an aftermarket flywheel to be used on several different rotary engine applications, this balancing mass is eliminated from the design of the rotary flywheel. However, this critical balancing mass must be replaced with an alternative balance weight or risk severe engine damage due to an "unbalanced" engine. A convenient alternative is to install an appropriate rear counterweight from an automatic transmission-equipped RX-7. Racing Beat offers this counterweight separately if needed.
Rear Counterweight (Required)
All Racing Beat flywheels require the use of an automatic transmission rear counterweight for correct operation. This required Mazda rear counterweight can be ordered separately as needed, see the chart below.
Flywheel Counterweight Chart
1974-82 12A (Mazda # 1883-11-751A)
1974-85 13B (Mazda # 1029-11-751A)
1983-85 12A (Mazda # N226-11-751A - discontinued by Mazda)
1986-88 13B All (Mazda # N3Y8-11-52X)
1989-95 13B All (Mazda # N3Y2-11-52X)
2004-11 13B RX-8 (Mazda # N3Z2-11-52X)
Installation Hardware: Racing Beat Flyweight kits include the flywheel unit and the appropriate mounting hardware, which includes the appropriate tensile-strength hardware to attach the pressure plate to the flywheel. DO NOT use other aftermarket flywheel mounting kits with the Racing Beat flywheels. l.
We strongly recommend replacing the throwout bearing (1971-78 - bearing and spring) or (1979-82) during any clutch work to ensure trouble free performance. Also, we recommend replacing the transmission front and rear seal kit when re-installing the transmission to reduce the possibility of leakage.
Safety Warning: None of the flywheel or clutch components shown in this site should ever be allowed to exceed 10,500 RPM under any condition. This same RPM limit applies to stock components. You must use an engine RPM-limiter to prevent excessive RPM. If your engine is capable of exceeding 8,500 RPM you must install a transmission scatter shield, or ballistic blanket. Failure to implement the above may result in serious injury or even death.