qc97z

iTrader: (9)

Hey guys-

I picked up a Fidanza flywheel for dirt cheap, but it's neutral balanced. According to Fidanza's application guide, the flywheel should come with external balance weights in the hardware kit (when new). I'm not 100% sure (I'll have to check when I get home from work) if the hardware I got with the flywheel has any weights in it.
My question is this: Can a neutral balance flywheel be used on a stock LT1, and use some a fluidampr or something on the front to "balance out the imbalance" caused by using a neutral flywheel?
Or should I just use a stock flywheel and sell the aluminum one?

draggin97s10

iTrader: (2)

No it cannot. From the factory they are rear balanced only, front neutral. You will have to get the weight for the findanza..i have the flywheel.. i like it.

Jerry Clayton

If you can't get the weights from them, I can balance the flywheel to the factory external specs

AChotrod

iTrader: (17)

Ya the rotating assembly has to be internally balanced not to use a weight on the flywheel.

gregrob

iTrader: (8)

You plan on starting a shop?

qc97z

iTrader: (9)

Jesus GregRob, I knew you'd have some smartass bullshit comment.
Please provide a beneficial answer, or don't post at all.

Thank you to all that had constructive things to say. I was thinking along those lines, but just wanted to verify. A second opinion never hurt anybody.

97lt1stroker

iTrader: (1)

I assume you are familiar with these engines. and flywheels. maybe you can help me. I just bought a 97 f body with a lt1 383 stroker. the motor vibrates really harsh. after speaking with previous owner. he said he used an internally balance rotating assembly with Callies dragon slayer crank, Scat rods and weisco pistons. he said it was a matched kit. he also told me he put a new OEM steel flywheel from the dealer. if my research is correct the oem flywheel would be for an EXTERNALLY balance in rear stock LT1? I hope a replaced correct flywheel is my issue thanks for input. also can I get a neutrally balanced LT1 flywheel to replace it with?

HomeSchool

My 96 trans am LT1 had a bad flex plate and the replacement was externally balanced. IIRC the LT1 IS an externally balanced engine. However I am not positive, and the automatics might differ from the manuals. I would suggest working your way up the trouble shooting ladder. Get a balanced flywheel see if it solves the problem. Being a 383 custom build, you might need to start tearing the engine down to locate the source of the imbalance

93M6Formula

He hasn't been online since last October and this thread is 4 years old. Would be best to start a new one.

SS RRR

iTrader: (2)

Stock the LT1 is externally balanced in the back via flywheel/flexplate and internally balanced in the front. The damper is not a balancer. There is no heavy side, regardless of what anyone tells you. If you see holes drilled into your damper that don't match someone else's that doesn't mean it is used as a balancer. Those holes are nothing more than to zero balance the damper. This is why it is not keyed and there is no need to reference the damper when uninstalling/installing.

BALLSS

for a internally balanced 383 you DO NOT want a stock/factory flywheel. you can have a factory FW neutral aka "zero" balanced by a machine shop (they will grind off the cast on weight and drill elsewhere on it or add pins to some outer holes in the process)

If you use a stock FW on a internal balanced motor it will vibrate and shake like a dog shiating razor blades

you can also buy aftermarket neutral balanced FW's...but IMHO always have them checked by a machine shop. Everyone I have was not exactly "zero" balanced. They get the PP zero balanced also

usually costs about $40-$50

waltsfastz

iTrader: (4)

I made this same mistake many years ago. engine viberatd like hell. Bought an SLP lightweight that SLP said was Neutral balanced. Didnt viberate as bad but still viberated like hell.
3rd time I pulled it out and took it and got it balanced. Ended up replacing the bearings where it had start to wear exesive in around 50 miles.

Spartan7

iTrader: (7)

From what I've been told, those weights are to trim out any slight imbalance in the front of the rotating assembly. Yes, the balancer is neutral balance. However, the GM manual specifies that in the event it is replaced, those little weights need to be transferred to the new balancer. That would mean they're not balancer-specific.

SS RRR

iTrader: (2)

Those must have been ultra rare because in all the years on the forums I've never seen a pic of one with added weight nor read anyone having one issue with installing the hub in whatever direction they so chose. Supposedly the hubs for these weighted dampers were not keyed which makes it a little suspicious.

Spartan7

iTrader: (7)

I haven't either, I found it by accident leafing through the GM manual. It confused me too, because I'd always heard they were neutral. But, it's in there. Not being keyed doesn't really apply because GM also describes how to install it (#1 TDC, etc). I'm not arguing with you, I doubt it even matters. But it's in there.