Flywheel

A Flywheel is a device attached to the rear of the crankshaft on the engine. It provides three main functions for the car:

• Provide a way for the starter to rotate the engine.
• Store energy in the form of rotating energy between combustion strokes.
• Transfer rotational force from the engine to the clutch & transmission.

The automatic-transmission equivalent of a flywheel is called a flex-plate. It provides the same basic function, but mounts the torque converter rather than a clutch.

A stock TT flywheel.

Variations & Specifications

There are multiple variations and versions of the flywheel as defined in the table below.

	Non-Turbo (MT)	Twin Turbo (MT)	Auto Transmission
90-95	Diameter: 317mm Weight: ???	Diameter: 321mm Weight: 23lbs	Diameter: 317mm Weight: ???
96*	Diameter: 317mm Weight: ??	Diameter: 321mm? Weight: 23lbs?	Diameter: 317mm Weight: ???

Note: 1996 USDM flywheels have a different part number, but are functionally identical. The 1996 MY has a hall effect sensor on the transmission that is triggered by the teeth on the ring gear.
Note: Torque bolts to 61-69 ft-lbs in a skip-2 pattern.

Ring Gear

Ring gear outer diameters:
NA: 12 7/16"
TT: 12 5/8"

Upgrades

Flywheels are a common upgrade for Z32s. Over years of usage, their surface becomes uneven and worn, prompting replacement, which usually leads to upgrading.
Most aftermarket flywheels are designed with light weight in mind. Because flywheels store energy between combustion strokes of the engine, a heavy flywheel results in a smoother-running engine and smoother clutch engagement, but at the cost of greater rotating mass, reducing engine response. Performance-minded enthusiasts often sacrifice minor drivability comfort for quicker engine response and less parasitic drivetrain loss.

Flywheels are often replaced/upgraded with clutches.

Replacement

Flywheels can be replaced any time the transmission has been separated from the engine. Simply remove the clutch & pressure plate assembly, then remove the bolts for the flywheel. when replacing clutch and pressure plates, it's often a good idea to have the flywheel replaced or resurfaced to ensure smooth operation.

Upon installation, flywheel bolts should be torqued to 61-69 ft-lbs.