SPEC Single Mass Flywheel

SPEC Single Mass Flywheel Upgrade For VOLVO M66

The Spec single mass flywheel is designed to be a 100% direct replacement for the dual mass flywheels fitted from the factory on M66 AWD 6-speed manual gearbox equipped models. The flywheel is machined from billet steel and is significantly lighter than the heavy dual mass flywheel. The single mass flywheel was designed with the performance enthusiast in mind, and works best on vehicles performance tuned for additional power and who don't mind slight clutch chatter during idle. The single mass flywheel is designed to be compatible with SPEC Stage 3+ clutch kit and SPEC Stage 5 clutch kit and comes preassembled with 10mm dowel pins for the clutch kit.

Original Dual Mass Flywheel: 26.1 pounds

Single Mass Flywheel: 17.75 pounds

The noticeable difference: A lot more engaging and easier / faster to shift compare to stock dual mass flywheel due to lightened flywheel. It does have small knocking sounds when idle. 

Be aware that because the single mass flywheel lacks the damping springs of a dual mass flywheel, any kit installed using this flywheel WILL result in clutch chatter at idle. This is normal and will not damage any components, nor will it effect the life of any related part.

The slave cylinders to order would be:

Slave cylinders:

P2 M56 (turbo and NA): 31259445
P2 M66 All: 31259889
P1 M56 (Non-turbos): 8675052
P1 M66 (Turbos): 31258380