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Discussion Starter #1
Can anyone confirm that engine rattle (sounds like a tractor) while idline which is lessened if I up the RPM's or engage the clutch is normal? I also noticed it after having the clutch upgraded to the full UUC kit.

thanks,
Chris
 

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what you describe sounds like the typical trans roll over noise that you get when you eliminate the dual mass flywheel.
 

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Discussion Starter #3
mottati said:
what you describe sounds like the typical trans roll over noise that you get when you eliminate the dual mass flywheel.
Thanks, can you explain the dual-mass flywheel and why the new one is noisier?

C
 

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cstucker1123 said:
Thanks, can you explain the dual-mass flywheel and why the new one is noisier?

C
Check the UUC website for an good explanation of what is happening. A few people have had success in virtually elimating the rollover noise by having the idle speed raised 2-300 rpm.
Regards,
Jerry
 

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Discussion Starter #5
gsfent said:
Check the UUC website for an good explanation of what is happening. A few people have had success in virtually elimating the rollover noise by having the idle speed raised 2-300 rpm.
Regards,
Jerry
Thanks, you were right on.

C
 

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Roll over noise is caused by vibrations from the small amount of lash in gears and the vibrations from the bearings on the input shaft. Once you take the load away (clutch in), or increase a load (extra revs) the noise settles out. The extra weight of the dual mass flywheel dampens out these vibrations, so they arent felt or heard.
Roll over noise with UUC setups or any non dual mass setup varies car to car. Differences in internal tolerances and wear make a difference in noise. Powerchip cured this for board member MIB as stated above, so if it annoys you maybe it is time for a powerchip! Get some more ponies and better throttle responce on top of killing the roll over noise.
I should find a chip to raise the idle on my buds 350Z. Stock that thing has a fair amount of roll over noise, but thankfully you can only hear it from the outside.
:cheers:
 
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