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RS Clutch + LWF noise ?

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Old 11-29-2012, 09:05 PM
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holsen12
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Default RS Clutch + LWF noise ?

I just had an RS clutch and LWF installed, and its' noisy between 1700-2000 RPM. This is the factory part, not an aftermarket part. The engine spins up and down more freely and the bottom end torque has improved which is very nice and my shifts are much quicker (RPM matching to gear selection). But it sounds like rattling sheet metal. Not irritatingly loud, but the other day I had my wife in the car and she (again) questioned my obsession with Porsche 993.

The dual mass was both quiet and seemingly smoother even if it did weigh 40+lbs. I can’t believe Porsche would design something that is unnecessarily noisy, or is it that our 3.6 engines have some inherent harmonic imbalance at that RPM range that the dual-mass overcame because it was also a harmonic balancer?

Is this typical ? Does anyone have a 'quiet' RS/LWF ?
Old 11-29-2012, 09:07 PM
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GT9111
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The sound is normal.
Old 11-29-2012, 09:09 PM
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goofballdeluxe
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The noise is totally normal. From what I understand the rattling noise is gear lash, inherent when you install a lightweight flywheel.

It's the price you pay for less weight and the engine spinning up faster.
Old 11-29-2012, 09:27 PM
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Quadcammer
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man, i'm really on the fence about this. On one hand, I'd like the improved responsiveness, but on the other, its a street car that shouldn't make such crappy noises. It seems silly to put in a new DMF, but I don't think I want such blatant rattling.

anybody got a video of this noise.
Old 11-29-2012, 09:30 PM
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jakfrost
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Hmm, I only get the rattling in neutral with the clutch out. As soon as I push it in the noise goes away.

Never had any 'rattling' when driving...? Or are you not driving, just reving the engine up to 1700-2000rpm...? If you are in neutral with the clutch out then it seems it is perfectly normal.

I personally don't find it much of a nuisance but then I have owned a few Ducati's, and am pretty familiar with a clutch 'rattle', hahaha.

Jim
Old 11-29-2012, 09:33 PM
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NineMeister
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The noise is caused by backlash in the non-engaged gears being shaken by the torque impulses of the engine at low rpm. It's totally normal and does no harm whatsoever, however if you don't like the noise because you drive around in 4th gear at 30mph all the time, then clearly the LWF package is not for you. This is why Porsche deemed the LWF suitable for the RS Clubsport only and an option on the 993 RS lightweight. If you wanna go faster there is always a price to pay somewhere along the line.
Old 11-29-2012, 09:55 PM
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jhg41977
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When I installed the rs clutch and lwf, it seemed a bit loud and kind of like it was going to fall apart in that same rpm range. A few months later I installed a set of sport cats and stage IIs from FD Motorsports. I must have bumped something during the install because the rattling noise went away.

Yes it is my daily driver during the good weather months.

All joking aside, you will learn to work with it. I found if I avoid certain situations, 2nd gear below 2200rpm for example, the noise is not present.
Old 11-29-2012, 09:57 PM
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holsen12
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I usually drive with RPM's around 4K+. But when I'm stuck in stop and go traffic, or banging around town, it's noisy.

I DO like it better than the DM, but wondering if there's an alternative...
Old 11-29-2012, 09:59 PM
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holsen12
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Perhaps I'm mistaken, but aren't the springs in the clutch friction disk supposed to dampen these transient vibrations ?
Old 11-29-2012, 10:02 PM
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jhg41977
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I think the springs are to soften the engagement of the clutch.
Old 11-29-2012, 10:02 PM
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M. Schneider
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The noise you've discribed is normal. Remember, the NVH character of the 993 trends lower than the previous 964 series 911. The RS LWF in a street car somewhat defeats this trend.

So okay you've got the RS LWF installed what next; enjoy the 3.6s new found performance, shift later and turn up the radio...
Old 11-29-2012, 10:15 PM
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ABCar
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Don't do the crime if you can't do the time.
For me, the little extra clatter is way worth the gain.
Old 11-30-2012, 02:52 AM
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Had the LWF for 1 year now and I love the rattle when the gearbox is warm. It sounds modified and that's what I like. It adds to the car's character if you ask me.
I sometimes get looks when in a crowded parking lot but every once in a while somebody understands what that rattle is.
The added responsiveness is well worth the rattle if you ask me.
I think you'll get used to it after a while.
Ed
Old 11-30-2012, 03:11 AM
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Mike J
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Funny, I did not get this when I put my RS clutch package in - I got the rattle when idling in netural, but as soon as the clutch pedal was in, it was quiet, and during driving no weird noises. Maybe it depends on the state of the transmission, or the oil you use, or maybe I need to get my hearing checked... :-)
Old 11-30-2012, 06:39 AM
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dgmattingley
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I get the same noises described here, which I assume are further exacerbated by my Wevo mounts and rs tranny mount. I like the idea of louder FD mufflers


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