REAR COUNTERWEIGHT, 13B 74-85 RX7

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• 

  FLYWHEEL ALUMINUM, 83-92 RX7 NON-TURBO NO COUNTERWEIGHT

  Aluminum Flywheel, 83-92 Non-Turbo – Requires Counterweight
  

  Applications
  This RX-7 flywheel is best-suited for use on high performance street, autocross, track, and racing applications. The performance benefits of an aluminum flywheel are well-established: improved throttle response, quicker engine revving, and improved shifting efficiency.

  Although aluminum Flywheels can certainly be used for daily-driven RX-7 street vehicles, the modest torque output of the earlier 13B engine combined with the reduced mass of the aluminum flywheel will require a bit more technique during clutch engagement when starting the vehicle from a standing start.  This is especially true when using a higher clamping force pressure plate and more aggressive clutch disc. If this is a concern, you may want to consider our Lightweight Steel RX-7 Flywheel as an alternative.

  Precision Machining
  The RX-7 aluminum flywheel kit both reduces the flywheel weight up to 55% and reduces the flywheel inertia up to 80%, as compared to the Mazda Factory OEM cast iron component.  Precision CNC machined from 6061-T6 aluminum, our flywheel assembly is mated to the  Mazda OEM ring gear and finished with an extremely durable, and easily replaceable clutch disc friction plate. Each friction plate is machined from A-36 steel and hardened using a ferritic carburizing heat-treating process, creating an extremely durable clutch disc contact surface. The friction plate is retained to the aluminum flywheel unit using aircraft-spec bolts and lightweight nuts. 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
  1981-85 RX-7 Stock Flywheel: 23 lbs
  1986-88 RX-7 Stock Flywheel: 24 lbs
  1989-92 RX-7 Stock Flywheel: 22 lbs
  Aluminum Flywheel: 12 lbs (including required counterweight)

  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 aluminum 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. We offer this counterweight separately if needed.

  Rear Counterweight (Required)
  All aftermarket flywheels require the use of an automatic transmission rear counterweight for correct operation.

  Installation Hardware
  Our Flywheel 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 our flywheels.

  We strongly recommend replacing the throwout bearing 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.

  SKU:

  11434

  $577.50
  Add to cart
• 

  PULLEY ECCENTRIC, SINGLE BELT ALUMINUM

  Racing Beat Aluminum Single Belt Eccentric Pulley 74-92

  O.D.: 3 7/32″

  SKU:

  11473

  $91.69
  Add to cart
• 

  NUT FLYWHEEL, FLYWHEEL/ECCENTRIC

  

  Flywheel Nut, Flywheel/Eccentric Shaft

  SKU:	11-711C-0810
  Manufacturer SKU:	0810-11-711C

  $31.43
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• 

  ENGINE FRONT COVER, THRUST BEARING 70-92

  

  Front Engine Cover, Thrust Bearing 70-92
  Two needed per engine

  SKU:	11-505B-0813
  Manufacturer SKU:	0813-11-505B

  $30.14
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• 

  PULLEY ECCENTRIC, 79-92 2 BELT ALUMINUM

  Racing Beat 2 Belt Aluminum Eccentric Pulley, 79-92 

  O.D.: 3 7/8″

  The Racing Beat Aluminum Double Sheave Main Drive Pulley for virtually all 1974-92 12A and 13B engines is designed for high performance/RPM street and moderate racing use, slowing the water pump and alternator 13-15 %, thereby reducing cavitation and power loss. If used with our Aluminum Alternator Double Sheave Pulley, you can have a true dual belt system. The stock air conditioning pulley is accommodated. Timing marks are provided at 10 degrees ATC,  0 degrees (TDC), 10 degrees BTC, and 20 degrees BTC. The weight of this pulley is 16 oz.

  We do not recommend this underdrive pulley be installed on “street” driven cars that are used for stop-and-go driving. In addition, we do not recommend the use of this underdrive pulley on 1987-91 RX-7 Turbo II engines unless modifications have been made (shorter intake runners, etc..) to increase the engine’s RPM range substantially. Turbo II engines produce their peak power in a lower RPM range, relative to a non-turbo engine.

  Note: It is not practical to offer a standard replacement belt due to the variations in engine configurations. After measuring the distance required for your application, we suggest you contact your local auto parts store to obtain the required 3/8-inch wide replacement belt.

  SKU:

  11469

  $118.43
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• 

  FRONT COUNTERWEIGHT, —NLA— 13B 74-85

  

  FRONT COUNTERWEIGHT,  13B 74-85

  Sorry, this item has been discontinued by Mazda.

  We sell used Counterweights on our Ebay Store (Mazdatrix1)

  SKU:	11-5110-N304
  Manufacturer SKU:	N304-11-511

  $0.00
  Read more