600145-03 is a flywheel kit for Mazda RX-8 applications and comes complete with an ACT counterweight. The flywheel counterweight is required when installing the XACT flywheel on Mazda RX-8 rotary applications. ACT XACT Streetlite flywheels are considerably lighter than stock and are the most durable flywheel offering from ACT. Materials are properly distributed for maximum strength, lower inertia, good heat tolerance and rigidity. ACT’s Streetlite flywheels are preferred for street or drag racing. XACT flywheels are serviceable and can be resurfaced with no need to purchase additional parts.

Feel
Noticeably improved engine response and acceleration, OE to mild gear rattle

Life
Heat-treated forging for strength and toughness, induction-hardened ring gears for maximum life

ACT Difference
Forged, CNC machined and dynamically computer balanced for smooth high RPM reliability