Lightweight flywheel without the noise?

nameless · 04-09-2010, 04:39 PM

Sorry, was trying to clear up a misconception...
Regarding the original question. It is actually gear rattle/lash that is taking place.
The noise is inside the tranny from the input shaft not being dampened by the dual mass flywheel. This makes sense when you think about when the noise is actually happening.
You are starting from a dual mass flywheel and going to a lighter single mass flywheel. Dual mass flywheels are used because of its properties with inertia - while harder to change the rotational speed - the benefit is that the power pulse transitions are smoother essentially cushioning the noises that would otherwise create gear rattle. Going to a lighter single mass flywheel you lose the vibration dampening benefits from the mass you lost.

The best way to mitigate this is by using a sprung hub which should help dampen pulses and changing to a heavier weight transmission oil. Dont think it is a question of what flywheel doesn't cause gear lash (the answer would be OEM), but if there is a combo that people have used that minimizes gear lash. I've used OS-G & Exedy combos in my car in the past, no issues - but it was on an FD (apples to oranges, since power delivery is different).

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04-09-2010, 04:39 PM	#15 (permalink)
nameless Base Member Join Date: Dec 2009 Location: Franklin, TN Posts: 5 Drives: Nothing Rep Power: 17	Sorry, was trying to clear up a misconception... Regarding the original question. It is actually gear rattle/lash that is taking place. The noise is inside the tranny from the input shaft not being dampened by the dual mass flywheel. This makes sense when you think about when the noise is actually happening. You are starting from a dual mass flywheel and going to a lighter single mass flywheel. Dual mass flywheels are used because of its properties with inertia - while harder to change the rotational speed - the benefit is that the power pulse transitions are smoother essentially cushioning the noises that would otherwise create gear rattle. Going to a lighter single mass flywheel you lose the vibration dampening benefits from the mass you lost. The best way to mitigate this is by using a sprung hub which should help dampen pulses and changing to a heavier weight transmission oil. Dont think it is a question of what flywheel doesn't cause gear lash (the answer would be OEM), but if there is a combo that people have used that minimizes gear lash. I've used OS-G & Exedy combos in my car in the past, no issues - but it was on an FD (apples to oranges, since power delivery is different).