600140-01 is a flywheel kit for various Mazda RX-7 and RX-8 applications that comes complete with an ACT counterweight. The flywheel counterweight is required when installing the XACT flywheel on various Mazda RX-7 and RX-8 rotary applications. XACT Prolite flywheels are ACT's lightest flywheel offering with lowest inertia. Prolite flywheels are designed for best throttle response and acceleration. Prolite flywheels are preferred for road racing or rally racing, and have reduced drivability. Materials are properly distributed for maximum strength, lower inertia, good heat tolerance and rigidity. XACT flywheels are serviceable and can be resurfaced with no need to purchase additional parts.
Description
Feel
Dramatically improved engine response and acceleration, mild to moderate gear rattle
Life
Solution heat-treated forging for strength and toughness, induction-hardened ring gears for maximum life
Quality
Assures correct external balance
Recommended Use
Recommended for race use
ACT Difference
Forged, CNC machined and dynamically computer balanced for smooth high RPM reliability
Can I use an aftermarket flywheel with an ACT clutch?
The ACT clutch system is designed to work with both stock and good quality aftermarket flywheels. Inferior aftermarket flywheels may have trouble with warpage or high wear. When replacing a flywheel, be sure that the
new flywheel meets the same specifications, such as proper step, ring gear tooth count, flywheel thickness, ring gear offset, etc. If the ACT clutch is designated as part of a conversion kit, then it must be used
with only the corresponding ACT flywheel.
What is a flywheel step?
The flywheel step determines the proper working range of the pressure plate and is extremely crucial for the clutch to work properly. The step is the distance between the friction surface and the pressure plate
mounting point on the flywheel. Depending on the make and model of the car it can either be an UP step or DOWN step and sometimes the flywheel will be flat (zero step). Check the manufacturer's specifications about
the proper flywheel step for the application.
Can the XACT Flywheels be resurfaced, and is there a special process?
Yes, ACT XACT flywheels can be resurfaced just like a stock flywheel and there is no special process other than using a flywheel grinder in good condition to remove as little material as possible for full cleanup (no
more than 0.040” / 1.02mm may be removed). Make 100% sure that the proper flywheel step is maintained as this will affect the clutch function if incorrect.
