Aluminum flywheel chatter
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Joined: Nov 2002
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From: Panama City FL
Aluminum flywheel chatter
Brand new SPEC and Fidanza combo installed by MTI in Houston. Too much chatter for my liking, but moderate and hard launces are no problem. It's the parking lot speed clutch engagement that cause the chatter. MTI says this is normal; will it go away? It's got over 1500 miles on it, but I can't really tell if it's any better. What to do?
Drifting
Joined: Mar 2006
Posts: 1,665
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From: FL
I just had a new clutch with lighweight aluminum flywheel installed this week, along with some other mods. I'm still in the break-in period so I have to drive easy. I noticed some chatter while stopped at lights, but not while starting up in first or while the clutch is engaged. I'm just chaulking it up to the aluminum would be a better conductor for chatter over the stock heavy steel wheel and it doesn't bother me. It reminds me of how my '71 Trans Am sounded (old school)
Pro
Joined: Jan 2003
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From: Tampa fl
What exactly does "chatter" mean? Is that when you start from dead stop and as you release the pedal and the car starts to move forward you get an unwanted vibration from the drive train? Or is "chatter" some sort of sound that it is making? I am considering one of these flywheels for my car but I do not want to sacrifice driveability. I have also been told that having a lower gear such as 4.10 would help this issue because the engine does not have to work as hard to move the car from a stop.
Clutch experts please help explain what is happening.
Clutch experts please help explain what is happening.
Team Owner
Joined: Mar 1999
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From: At the beach in little Rhody
I have only driven one car with the aluminum flywheel. I wasn't nuts on it but did find you needed to give it a little more throttle starting out to keep it from doing what you describe. I would say unless its really bad chatter like a bad clutch, it is normal. Try a little more gas as you start out from a dead stop.
Safety Car
Joined: Apr 2004
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From: San Bruno ca
I use to have a spec 3+ with the aluminum fly wheel and had the same amount of chadder as you do. I hate to say it but it is pretty common with the spec clutch. I had mine change out after 5k miles and the spec was just about toast by then. I end up going with a Cartek clutch and back to a steel fly wheel and the chadder is all gone. 
Team Owner
Joined: Mar 2001
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From: small town in S.E Pa. PA
St. Jude Donor '03-'04
Very common problem with a light weight flywheel... what you are experiencing is a learning curve... it takes some getting use too, but very very normal.. a couple of weeks from now you wont give it a second thought...the heavy flywheel is very forgiving.... You will be ok,,,
Bill aka ET
Bill aka ET
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Pro
Joined: Jan 2003
Posts: 526
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From: Tampa fl
Is the chatter being caused by the flywheel or the pressure plate and disc? Are the spec clutches prone to chatter with the steel flywheel also? What about using a Z06 pressure plate and disc with the lightweight flywheel?
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Joined: Nov 2002
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From: Panama City FL
Thanks
I appreciate all of your input. The chatter is annoying, but not undrivable. I can easily add more throttle position and accelerate smoothly, but those times when slower folks are in my way or when I'm maneuvering through a crowded parking lot, I hate to rev the engine and appear like I don't know how to drive a manual.
Team Owner
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From: small town in S.E Pa. PA
St. Jude Donor '03-'04
these references to 500 miles and 4000 miles, are not really accurate.
while they may represent an individulas thought process, they really reference how long it took them to get use the the launch ( get the car moving ). There is really no dramatic break in period, the flywheel surface is ready to accept the clutch disk the minute it is installed.. engaging the disk to flywheel take some getting use too..
while they may represent an individulas thought process, they really reference how long it took them to get use the the launch ( get the car moving ). There is really no dramatic break in period, the flywheel surface is ready to accept the clutch disk the minute it is installed.. engaging the disk to flywheel take some getting use too..
Safety Car
Joined: May 2000
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From: Albuquerque NM
Actually the 500 mile breakin was from the manufacturer. And he was right. After that, no more problems with chatter. The change I had to make i.e. a few more revs for a smooth takeoff took maybe a day or two to become automatic.
Drifting
Joined: Jan 2003
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From: Springfield MO
St. Jude Donor '05
The chatter nor the "parking lot engagement" feeling will change. Spec clutches are notorious for chatter. The low rpm engagement is a tradeoff with the aluminum flywheels. You can rev quicker but you have to rev it a little higher on launches or it feels sluggish...that's the tradeoff.
Most get used to the aluminum flywheels but I never did. I had my LUK Pro Gold installed with the aluminum fly. I figured what the heck, I'll take the additional hp. Well, it was a bad decision on my part to go with a mod without really researching it. I have since switched back to a steel fly and the drivability is much more to my liking.
I think you might be stuck with the chatter because its most likely a symptom of the Spec clutch, not the flywheel. But, you might be able to switch to a steel flywheel to get back to a more "stock" feel on launches.
Most get used to the aluminum flywheels but I never did. I had my LUK Pro Gold installed with the aluminum fly. I figured what the heck, I'll take the additional hp. Well, it was a bad decision on my part to go with a mod without really researching it. I have since switched back to a steel fly and the drivability is much more to my liking.
I think you might be stuck with the chatter because its most likely a symptom of the Spec clutch, not the flywheel. But, you might be able to switch to a steel flywheel to get back to a more "stock" feel on launches.
Team Owner
Joined: Mar 2001
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From: small town in S.E Pa. PA
St. Jude Donor '03-'04
Originally Posted by 6Speeder
Actually the 500 mile breakin was from the manufacturer. And he was right. After that, no more problems with chatter. The change I had to make i.e. a few more revs for a smooth takeoff took maybe a day or two to become automatic.
Heel & Toe
Joined: Dec 2004
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From: ALVA FL
Originally Posted by Evil-Twin
these references to 500 miles and 4000 miles, are not really accurate.
while they may represent an individulas thought process, they really reference how long it took them to get use the the launch ( get the car moving ). There is really no dramatic break in period, the flywheel surface is ready to accept the clutch disk the minute it is installed.. engaging the disk to flywheel take some getting use too..
while they may represent an individulas thought process, they really reference how long it took them to get use the the launch ( get the car moving ). There is really no dramatic break in period, the flywheel surface is ready to accept the clutch disk the minute it is installed.. engaging the disk to flywheel take some getting use too..
Thread Starter
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Joined: Nov 2002
Posts: 98
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From: Panama City FL
More Thanks
Again-
Thanks for all the input. Even with all the information, the truths seems to be a blend of many posts. The clutch was originally installed without the shim, and I drove the car for 600 highway/some city miles, but could hardly get the car into gear, especially when drivetrain heated up, but had almost indistinguishable chatter. I had the shop reinstall w/shim (meaning that engagement takes longer, or more pedal throw) and now gettting it into gear is easy, but chatter was worse. Along with launching with more throttle, today I made about 6 hard launches at 2-3K with some power shifting up the range. On the way home, the clutch was dramatically better (greatly reduced chatter), but I wonder if it will remain. If it stays better, and the chatter diminishes, then I would recommend 500 mile break-in to ensure resonable heat cycles, then a half a dozen hard launches. Rregardless of what the manufacturer's say, It appears that this particular set-up may be helped by bedding-in the clutch. Any other thoughts?
Thanks for all the input. Even with all the information, the truths seems to be a blend of many posts. The clutch was originally installed without the shim, and I drove the car for 600 highway/some city miles, but could hardly get the car into gear, especially when drivetrain heated up, but had almost indistinguishable chatter. I had the shop reinstall w/shim (meaning that engagement takes longer, or more pedal throw) and now gettting it into gear is easy, but chatter was worse. Along with launching with more throttle, today I made about 6 hard launches at 2-3K with some power shifting up the range. On the way home, the clutch was dramatically better (greatly reduced chatter), but I wonder if it will remain. If it stays better, and the chatter diminishes, then I would recommend 500 mile break-in to ensure resonable heat cycles, then a half a dozen hard launches. Rregardless of what the manufacturer's say, It appears that this particular set-up may be helped by bedding-in the clutch. Any other thoughts?