Alternator and Main Drive Pulley Set
74-92 Rotary Engines (All)
Part Number: pulleyset1
Sorry, this product is on temporary backorder.
Contact Racing Beat for ordering information
and expected availability date.
Addtional Photos - Select to Enlarge
Racing Beat RX-7 Pulley Set
Packaged as a pulley set, each kit includes one (1) alternator and one (1) main drive pulley.
Single Sheave Alternator Pulley (Part no. 11492)
This Mazda Competition Parts Single Sheave Alternator Pulley reduces alternator RPM approximately 20% from stock for street high-performance and racing use. For use on virtually all 1974-8-92 12A and 13B rotary engines, this aluminum underdrive pulley (3.2 oz) is intended for use with the Single Sheave Main Drive Pulley, although it can be used with the stock main drive pulley. The pulley is bored 15mm for use on small shaft alternators, although it can be bored larger if necessary.
Single Sheave Main Drive Pulley (Part no. 11473)
Racing Beat's Single Sheave Main Drive Pulley for virtually all 1974-92 12A and 13B engines reduces the water pump/alternator drive ratio substantially to avoid water pump cavitation and alternator damage due to the extreme RPMs encountered in racing. This aluminum main drive pulley (6.4 oz) also reduces the engine's rotating inertia and the power loss to the accessories. The pulley is provided with a series of engraved timing marks at 0 degrees (TDC), 12.5 degrees BTC, and 25 degrees BTC.
We do not recommend this underdrive main 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 pulley on 1987-91 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.
Precision-machined from billet aluminum alloy, each pulley is finished with a hard anodized surface treatment to ensure superior longevity and excellent abrasion resistance. As compared with standard anodizing processes (typically identified by components finished with a bright red or blue finish), a hard-anodized aluminum component will offer comparatively superior durability and wear characteristics. Hard anodized components are typically identified by a darker surface coating, most commonly with a dark grey or black matte finish appearance.
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.