matt89

okay, how important is it to do this? I just bought a pp/disk and had the flywheel resurfaced and when it was all together, there was a slight vibration I could feel through the steering wheel that I didn't notice before, I was just wondering how many people have just bolted the stuff together and had the same thing happen...

Mike44138

iTrader: (3)

Not important if you're willing to replace input shafts, pilot bearings, bottom end bearings, crank shafts, clutches, or risk a catastrophic failure of a flywheel pressure plate or clutch disk.... It's cheap insurance. I have no idea why someone would go through all the effort to pull the trans, replace the clutch, and bolt it back up without spending the $50-$100 to know the assembly is balanced. Especially considering the cost of some of the parts for higher end clutches.

Your vibration could be from the drive shift not being put back in witht he proper alignment. The drive shafts are balanced and if they're not installed in the same position they're removed from you'll get that. Does it vibe stopped in neutral or does it only happen on the road?

matt89

no... it's there no matter what... stopped or moving at about 1200 rpms

Project GatTagO

iTrader: (7)

So that means it is from the engine. Take it apart, balance the flywheel and clutch as an assembly.

Andrew

matt89

hey... is the flywheel suppesed to be balanced to 0 everywhere (static) or does it need weight on one side? I rotated it and it's saying 35 grams heavy on one side! Good or bad?

Beast96Z

iTrader: (21)

I don't think that is correct. It is balanced, but it can be put back in either way. It's a sphere that rotates. There is no top or bottom. The rear or tranny would never know if it was installed like it was or 180* out. If that were the case, you'd have to balance the shaft with the tranny and rear attached. Kinda like wheels/tires. There balanced, but they don't have to be placed back on the exact lugs they came off of.

Matt, you want the assembally to be 0 balanced.

purple98haz28

iTrader: (5)

how do u balence the assembly. sorry this sounds newbish i am doing my clutch install next weekend and i don't know how to balance it

sgarnett

iTrader: (1)

You take the flywheel, pressure plate, and bolts to an automotive machine shop and have them balance it First, they need to balance the flywheel by itself, then add the pressure plate, check the balance, and do whatever needs to be done to the PP to get the whole assembly back to balanced.

Project GatTagO

iTrader: (7)

The whole assembly needs to be zero balanced, since LSx engines are internally balanced, unlike LT1s, etc...

Andrew

matt89

cool... i dropped it off at the machine shop to get it balanced! gonna cost me 80 bucks I think... Do you guys think I hurt anything driving it around for a half an hour with the flywheel out of balance? I hope not... but if it's as hard on the main bearings and everything as everyone is saying... crap! It could JUST barely be felt through the steering wheel and shifter when I could feel it.

Mike44138

iTrader: (3)

Matt, probably didn't do any major damage I wouldn't be concerned about it with that little driving.

Beast, I guess that makes sense. For some reaons I assumed the drive shaft was balanced with the yoke fromt he differential. I don't know for sure so I could be wrong. I was just always told to mark it and reinstall in the same alignment. Anyone know if the drive shafts are just neutral balanced by themselves or if the rear end yoke is connected when they do it?

Jditlfm

iTrader: (26)

So the Lt1 clutch assemblys dont need to be balenced? I ask because i had my flywheel turned and I installed the slp clutch late last summer without balencing it. Thanks

Jditlfm

iTrader: (26)

Any help?

matt89

ls1's are interanlly balanced, so the flywheel SHOULD be balanced to ZERO. LT1's on the other hand are EXTERNALLY balanced, so they need weights on the flywheel. either way, if you get the FW resurfaced, it needs to be balanced whether it's to zero or with a bias towards one side.

jyeager

Since everything is intended to be zero balanced, you must be saying that the manufacturer doesn't bother to balance flywheels or clutches. Yes?

Project GatTagO

iTrader: (7)

On LS1 engines the flywheel and clutch assembly are zero balanced together. So when you change clutches and keep the stock flywheel, you must once again balance the flywheel and clutch together.

On LT1 engines you should still have the flywheel and clutch balanced together. The difference is that the LT1 flywheel and clutch assembly are no zero balanced, but they have a specific "off balance" weight that must be maintained in the proper location.

Andrew

BULLET99Z28

iTrader: (9)

Driveshafts are balanced by themselves in a special balancer. I worked in a drivetrain repair shop-Everything from semi stuff to race car stuff. U do NOT have to put the driveshaft back in the same position. It is balanced B4 it ever goes into the car

DEE99TA

iTrader: (7)

What about the LS7 setup? With a LS2 flywheel and LS7 clutch, do these need to be balanced? Shouldn't they be balanced already?


DEE

jyeager

Thanks for adding your expertise here. I do know that I've read in my service manual (1970 Pontiac) that the driveshaft must be installed the same way. did they used to balance the driveshaft with the pinion? Why is/was this recommended by factory procedures?

jyeager

What I've been able to figure out is that the factory tolerances for balance on each item, when added up could be too much imbalance in some cases...but you'd be about as well off as any factory assembled car.

Someone said the factory tolerance for balance was 6 grams.

I'm thinking it's far more important when using an aftermarket clutch which may not have GM's quality control.