Harmonic Balancer confusion?
1/4 mile/AutoX
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From: Buffalo Texas
there is a thing called "google it" if you install a aftermarket balancer you are at the mercy of whatever God you believe in !!!! again the LS engine is externally balanced by the damper and flywheel setup !!!!!!!!!!!!!
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From: QC AZ
LOL...can't find anything to support your argument, can you?
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From: Western NY
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According to the factory shop manual, the stick shift cars are "hot balanced" after being assembled as a unit, and the small holes are used to insert equally small "balance weights", to allow for that last little bit of balance correction. I installed an ATI balancer on my car, and it has no provision for such things....
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From: Michigan
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From: South Hill Wa
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The LS1 engine is an internally balanced platform.
The reason that LS1 balancers new or aftermarket have holes in them is because they are balanced to themselves.
As someone else already mentioned, if it was an externally balanced engine the engine would a have key on the damper.
You can choose to argue this in whatever fashion you'd like.
OP, don't turn this into a rocket science that is not needed. Change your seal and put the thing on and torque to ARP specs and get to driving.
Last edited by Mr. Black; Sep 15, 2018 at 10:37 AM.
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1/4 mile/AutoX
Joined: Jun 2014
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From: Buffalo Texas
Using your words of "google it"
The LS1 engine is an internally balanced platform.
The reason that LS1 balancers new or aftermarket have holes in them is because they are balanced to themselves.
As someone else already mentioned, if it was an externally balanced engine the engine would a have key on the damper.
You can choose to argue this in whatever fashion you'd like.
OP, don't turn this into a rocket science that is not needed. Change your seal and put the thing on and torque to ARP specs and get to driving.
The LS1 engine is an internally balanced platform.
The reason that LS1 balancers new or aftermarket have holes in them is because they are balanced to themselves.
As someone else already mentioned, if it was an externally balanced engine the engine would a have key on the damper.
You can choose to argue this in whatever fashion you'd like.
OP, don't turn this into a rocket science that is not needed. Change your seal and put the thing on and torque to ARP specs and get to driving.
https://www.cadillacforums.com/forum...-balanced.html
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From: South Hill Wa
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I believe the engine is internally balanced, if the harmonic balancer was part of the balance it would be keyed like it was on older engines like the 454 that was externally balanced. Everything I have read on the internet except a few posts in this thread have said LS engines are internally balanced. Here are some links, the first says LS engines are internally balanced. I converted 454 from external to internal balance, it required new balancer and flywheel and having the internals balanced with heavy metal, did not need a clutch because it was a marine engine.
https://help.summitracing.com/app/an...l-vs.-external
The second has lots of good LS engine info and says stroker engines are balanced with heavy metal, engines balanced with heavy metal are internally balanced.
http://blog.jepistons.com/everything...-engine-family
https://help.summitracing.com/app/an...l-vs.-external
The second has lots of good LS engine info and says stroker engines are balanced with heavy metal, engines balanced with heavy metal are internally balanced.
http://blog.jepistons.com/everything...-engine-family
Last edited by jpb1978; Sep 15, 2018 at 12:28 PM.
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From: At the beach in little Rhody
According to the factory shop manual, the stick shift cars are "hot balanced" after being assembled as a unit, and the small holes are used to insert equally small "balance weights", to allow for that last little bit of balance correction. I installed an ATI balancer on my car, and it has no provision for such things....
You should be using the ARP lube on the ARP bolt threads, under the washer and under the bolt head. It should be provided with the bolt.
I would consider swapping the front seal since it is fully exposed. Since the Powerbond is a keyed damper, I would also consider the ATI pin kit that takes advantage of the key way in the damper hub.
Don't use ls1howto.com for instructions. Get a proper tool to press on the new damper. Follow the service manual up until the point that the new bolt is installed and then follow the tightening sequence for the ARP bolt.
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From: Homer Glen IL
The LS1 engine is internally balanced, and the flywheel and harmonic 'balancer' (really just a harmonic 'damper' on this engine) are neutrally balanced by design.
However, some of the manual transmission engines were failing a GM spec for vibration at the seat mount location at idle. Auto trans cars were passing the spec.
GM decided to do the 'hot balance' fine tuning on manual cars only. I hear it was a tight GM NVH spec that only some manual cars were just barely failing. Once you replace your flywheel or pressure plate that balancing done by the factory in the original balancer is meaningless anyways because it's a package deal with the other end of the engine.
I know a guy who worked in the engine test department for GM during development of the LS1.. they never bothered to do this fine balancing on any engine they tested. He assured me not to worry about it.
I hope that helps.
However, some of the manual transmission engines were failing a GM spec for vibration at the seat mount location at idle. Auto trans cars were passing the spec.
GM decided to do the 'hot balance' fine tuning on manual cars only. I hear it was a tight GM NVH spec that only some manual cars were just barely failing. Once you replace your flywheel or pressure plate that balancing done by the factory in the original balancer is meaningless anyways because it's a package deal with the other end of the engine.
I know a guy who worked in the engine test department for GM during development of the LS1.. they never bothered to do this fine balancing on any engine they tested. He assured me not to worry about it.
I hope that helps.
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From: Lake Charles, LA
Welp, it sure looks like I've started some arguments, whoops! But thanks for the info guys, I'm leaning towards the idea that it won't matter how the new one goes on. I have no way to adjust it anyways. I got my car up off the ground now and I'm as ready as I'll ever be to take on this project. I may update after finishing and driving for a while. Hopefully it all goes smoothly. Thanks again!
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interesting that GM themselves says otherwise. Not that I trust GM or anybody else for that matter. I got sick and tired of looking for a procedure to install the thing so I put the damn thing on. Same went for my clutch. I switched to a LS7 clutch and aluminum flywheel and threw it on the car. It spun to 7200 without any problem. But I've always wondered about this.
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From: Wisconsin
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