REAR COUNTERWEIGHT 83-85 12A
Rear counterweight for 83-85 12A Engines — they have the “N” on the rotors
These were discontinued by Mazda — We are having them made.
We took a few pair of 83-85 12A rotors, weighed them all for an average, set the bobweights for those weights on a 12A eccentric shaft then we re-balance NEW 13B rear counterweights to match.
SKU: | 11-751A-N226-MOD |
Manufacturer SKU: | N226-11-751A-MOD |
REAR COUNTERWEIGHT 83-85 12A
$317.43
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NON-TURBO Diameter MAZDATRIX ALUMINUM FLYWHEEL 83-92
83-92 NON-TURBO Diameter MAZDATRIX ALUMINUM FLYWHEEL
Mazdatrix designed aluminum flywheel.
With our flywheel the pressure plate bolts directly to the flywheel and uses the original style locating dowels, eliminating the need for separate spacers.
Comes with all necessary hardware.Flywheel is 11 3/4″ Diameter which fits ALL Non-Turbo Transmissions from ~1974-1991. It uses a 225mm CLUTCH which is standard from ’83 – 1991.
Weight is 7.6 POUNDS with hardware w/o counterweight.
Rear counterweight must be purchased separately to match the engine
Can be used on all 74-82 engines originally equipped with a 215mm clutch, but you must buy a 225mm 83-92 clutch.
Lighter than other ALUMINUM flywheels at 7.6 pounds versus theirs at 8.5 pounds.
SKU: 104806-11 Manufacturer SKU: 104806-11 -
ENGINE FRONT COVER, BEARING PLATE 70-92
Engine Front Cover, Bearing Plate 70-92
SKU: 11-5010-1011 Manufacturer SKU: 1011-11-501 -
FLYWHEEL ALUMINUM, 83-92 N/A 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 -
FLYWHEEL STOPPER TOOL, ALL Non-Turbo diameter flywheels
Flywheel Stopper Tool, All Non-Turbo diameter flywheels (Except RX-8’s)
Flywheel stopper makes getting the flywheel / counterweight nut off a LOT easier.
For flywheels 11 3/4″ diameter.SKU: 49-220NT Manufacturer SKU: 49-220NT -
FLYWHEEL Mazdaspeed RACE 5.5″, FOR 5.5″ RACE CLUTCH NA–NLA–
Race Flywheel for 5.5″ Race Clutch. Fits all non-turbo diameter bell housings. (11.75 diameter and 116 tooth)
3.9 LBS
Accepts 5.5″ clutch ONLY
Our Hardware Kit #284063-HW-5.5 will NOT work on this flywheel. Customer must supply their own hardware for this flywheel.
When using this flywheel, you MUST modify your rear counterweight with additional holes and reduce hub diameter.Sorry, this item has been discontinued by Mazda
Click here for a templateSKU: 02-9207-0000 Manufacturer SKU: 0000-02-9207 -
NUT FLYWHEEL, FLYWHEEL/ECCENTRIC
Flywheel Nut, Flywheel/Eccentric Shaft
SKU: 11-711C-0810 Manufacturer SKU: 0810-11-711C