Single Mass FW ID

[Hib Halverson]

Originally Posted by XfireZ51

The FW makes no noise. The noise is from the Trans which is a bit like rocks in a can. The Dual Mass absorbs the engine vibration.

A dual mass flywheel does not "absorb" engine vibration. The engine mounts and the car's structure do that.

The dual mass wheel damps gear rattle from the transmission.

At idle and low rpm the engine speed fluctuation caused by four firing impulses per revolution (engine speed increases as the engine accelerates during a power stroke then decreases as the engine slows down on a compression stroke) causes the teeth of the gears on the transmission main shaft to vibrate or rattle in the teeth of the gears on the countershaft

The dual mass wheel, partially damps the effect of this speed fluctuation by setting up a secondary fluctuation out of phase with the primary. The result is a reduction in gear rattle.