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LS6 Flywheel Balance

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Old Dec 1, 2023 | 03:51 PM
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Default LS6 Flywheel Balance

I'm swapping an LS6 into a C3 along with a TKX. I bought a new McLeod flywheel and Clutch from SST, and that's what's installed in the photo below.

I took another look at the flywheel that was originally on the LS6, that the PO allowed to rust outside. It seems to have some partial holes drilled at the perimeter (bottom of the photo). Is this for balancing, or just to static balance the flywheel after casting/machining? I thought the LS6 was internally balanced. Did the factory balance the clutch and flywheel together? Should I be concerned about any of this for my C3 application with all new (but unbalanced) parts?

I'm also considering cleaning up the rusty (and much lighter) LS6 flywheel and putting it on a junkard LM7 5.3 project. Any problem doing this, or should I just buy a new flywheel and not try to be so cheap?


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Old Dec 1, 2023 | 04:54 PM
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Hot balanced to the engine at factory. Field service manual is a good read.
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Old Dec 3, 2023 | 11:44 AM
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Read this:
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Old Dec 3, 2023 | 12:00 PM
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Originally Posted by ipuig
Read this:
Thanks!



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Old Dec 3, 2023 | 07:12 PM
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I have a question also, if you have a balanced and blueprinted engine, there would be no need to follow factory guideline, correct?
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Old Dec 3, 2023 | 08:23 PM
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What does a balance engine mean?
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Old Dec 3, 2023 | 09:36 PM
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So I 3D printed a "hub" and stuck the flywheel in a truing stand. There is no position in which the flywheel autocorrects, but this system certainly isn't going to find errors of a few grams.

What would you suggest? I could resurface this flywheel, and stick it back on my LS6 (which has a generic, presumably zero balanced McCleod flywheel). Or do I just send it with both, and hope for the best? As you can see, there are no balance weights on the old flywheel, just the suspicious holes from the initial zero.




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Old Dec 4, 2023 | 01:17 AM
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Every C5 C6, C7 Flywheel /pressure plate is Hot Balanced to the engine. When you remove your OEM flywheel, It should be MATCH MARKED to its OEM position on the CRANK. If it has balance pins, it had noticeable harmonics/vibrations that needed to be corrected. When reinstalling that OEM flywheel, it needs to be reinstalled in the same clocking position on that crank.

In your case, the flywheel has NO balance pins in its outer rim. You would have been one of the people that go to the tuners/shop and have an aftermarket clutch installed and never have any issues and never look back.

NOTE 1 If you are NOT using the original Torque Tube / rear trans/Diff layout, I DO NOT believe that the vibration/harmonic will be realized or noticed.
NOTE 2 The A4 Transmission C5s DO NOT have this issue and are not Hot Balanced.
If the engine that you are using is ,properly internally balanced and going into a car that used a conventional transmission bolted to the bell housing and a driveshaft, using a good zero balanced flywheel should be all you need to ward off the evil vibration devils.

Thats My 2 Cents.

BC
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Old Dec 4, 2023 | 08:01 AM
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Originally Posted by Bill Curlee
Every C5 C6, C7 Flywheel /pressure plate is Hot Balanced to the engine. When you remove your OEM flywheel, It should be MATCH MARKED to its OEM position on the CRANK. If it has balance pins, it had noticeable harmonics/vibrations that needed to be corrected. When reinstalling that OEM flywheel, it needs to be reinstalled in the same clocking position on that crank.

In your case, the flywheel has NO balance pins in its outer rim. You would have been one of the people that go to the tuners/shop and have an aftermarket clutch installed and never have any issues and never look back.

NOTE 1 If you are NOT using the original Torque Tube / rear trans/Diff layout, I DO NOT believe that the vibration/harmonic will be realized or noticed.
NOTE 2 The A4 Transmission C5s DO NOT have this issue and are not Hot Balanced.
If the engine that you are using is ,properly internally balanced and going into a car that used a conventional transmission bolted to the bell housing and a driveshaft, using a good zero balanced flywheel should be all you need to ward off the evil vibration devils.

Thats My 2 Cents.

BC
Thanks! That's just what I was hoping for.

No torque tube in a C3, so hopefully I'll be okay with both engines.
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