Red99TA

iTrader: (11)

So I know our motors are internally balanced but someone told me that weights are sometimes added to the flywheel at the factory to fix some minor imbalance issues with the motor. I just did a clutch swap on my car a couple weeks ago and looked at the stock FW/PP that I took out to check for these weights. I found two slugs on the flywheel that looks like they were pressed into 2 holes that were drilled through the flywheel. These holes are spaced evenly around the outside of the FW. It also has a different area with several spots drilled to remove material (not drilled all the way through). I noticed that the PP also has a couple of small weights that attach through the holes that are drilled around the PP. Is it true that these little slugs in the FW were for the motor balance and the areas that were drilled out on the FW were for balancing the FW/PP? I thought that GM balanced the FW/PP together to a neutral balance (hence the drilled out areas on the FW) and then if the motor needed any weights then they were put on the flywheel. The whole reason I ask is the new FW/PP was neutral balanced by McLeod and I've got a little more vibration than before. It's not bad just around 700-800 and 1800-2200 rpms that I notice it and the rear view mirror even shakes a tiny bit (very slightly blurs the image but almost unnoticeable). Wondering if I should've had the new FW balanced to match what the stock FW was at. Here's some pics of the stock parts with red circles showing the weights:

Red99TA

iTrader: (11)

Bump - someone's got to know the answer to this

jsz06

From my experience with the clutch on my 02 z06, you need to balance the clutch assembly as one unit from pp to fw, I had that vibration on my second clutch install and let it go for a while and then my rear main seal started leaking. Sorry to be the one who tells you,but if I were you I'd pull it off and have everything rebalanced. If you're a dyi like me, I feel for you.

Red99TA

iTrader: (11)

In my post I said that the FW/PP were balanced by McLeod. In fact I paid extra to have them balanced together as an assembly. The question is whether or not the stock setup uses any weights on the FW to account for motor imbalance. If so then having a new clutch/FW balanced together will result in some vibration unless the same weight is transferred to the new setup.

jsz06

That does not make any sense if everything was balanced together you should'nt have any vibration, I've gone through 3 clutches and the only one that vibrated was the second one because the flywheel was off 4 grams. and no you should'nt have to transfer the weights from your old set up.

JCS30TH

iTrader: (1)

I am getting ready to have mine pulled. Installed a new one because the pos hydralics went bad it and had terrible vibrations and chatter like a bitch. Had to pull a 2nd time and ask if it could be balanced. Machine shop said no, so I resurfaced the stock flywheel and installed. Was quite a bit better but still not right. Chatter is terrible (you can hear it 15feet away) and there is still vibration.

jsz06

Not sure how the balance is actually done, but mine always have a mark drawn on the pp and fw so that i can match up the marks at install. I think its bolted up to an ls crank not to sure about that though.

Red99TA

iTrader: (11)

My new setup did have a line painted on it so I could match the orientation of the PP, flywheel, and adapter ring. I just don't know whether or not I should've had the new FW matched to the old one since the old one has those 2 small weights in it. The vibrations occur when I'm sitting still in 1st gear with the clutch in (discs not rotating) so it's got to be balance-related on the FW/PP I would think.

Red99TA

iTrader: (11)

Just talked to LuK (manufactured the OE setup) and they claim that the FW/PP is balanced as a unit and that they are the ones that would've put the weights in the flywheel and that GM never did on the assembly line.