stock balancer weight?
Thread Starter
Burning Brakes
Joined: Jul 2002
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From: Nova Scotia
stock balancer weight?
Does anyone know the weight of the stock harmonic balancer on a wet sump engine? Curious how it compares to the ATI. Thanks
Last edited by hubes; Oct 28, 2020 at 10:02 PM.
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Its not a harmonic balanced that is off center weighted to balance the motor out, but a harmonic dampening that is even weighted with dampening section/ring instead.
Hence LS motor is internally balanced, so the HD only dampens the off frequencies of the crank from the pulley instead.
So on that note, if you are looking to lighten a HD, then ATI would be the way to go, since before you assembly it, you can go through the parts to remove weight from each of them one at a time.
With something like the PB1117SS, you could still lighten it, but since it still has the Bonded OEM style rubber band between the inner hub and outer sections, you really don't want to remove the C ring pull it apart.
Short bus, since the flywheel has more weight that can be reduced, and will dictate more of how fast the motor will rev up, your just better off going with a lightened fly wheel on the other end of the motor if you want the motor to rev faster/pick up more power that way.
Hence LS motor is internally balanced, so the HD only dampens the off frequencies of the crank from the pulley instead.
So on that note, if you are looking to lighten a HD, then ATI would be the way to go, since before you assembly it, you can go through the parts to remove weight from each of them one at a time.
With something like the PB1117SS, you could still lighten it, but since it still has the Bonded OEM style rubber band between the inner hub and outer sections, you really don't want to remove the C ring pull it apart.
Short bus, since the flywheel has more weight that can be reduced, and will dictate more of how fast the motor will rev up, your just better off going with a lightened fly wheel on the other end of the motor if you want the motor to rev faster/pick up more power that way.
Last edited by Dano523; Oct 29, 2020 at 12:46 AM.
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Thread Starter
Burning Brakes
Joined: Jul 2002
Posts: 1,136
Likes: 100
From: Nova Scotia
Dano: I understand about balancing engines, I'm really just curious about how it compared to ATI. But I would like to take this opportunity to thank you for all the info you contribute on this forum, I've read quite a few very informative posts by you.
torquetube: Thanks, looks like it's right in the middle between the steel and aluminum shell ATI
torquetube: Thanks, looks like it's right in the middle between the steel and aluminum shell ATI
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Hubes, where the ATI shines, is since the pulley is bolted to the hub, it holds a lot more Pulley torque, then say the PB unit that still has the rubber section bonded to the inner hub and outer pulley to prevent the two from slipping against each other.
The downside to the ATI pulley, is you need to removed it, this means that the pulley bolts have to be removed to get it down to the inner hub, and the pulley bolts need to trashed and replaced before the unit is reinstalled. Hence it not only the initial torquing, but the 272 loctite that is used when they are installed, that ends up stretching the bolts as they are being removed, to cause them to snap after the fact, if you try to reuse them.
On the PB unit, since it has exposed threaded channel on the inner hub to pull it that way, it's easy to pull and reinstall it with just replacing the HB main bolt alone.
Note, tend to use the oem stretch to torque bolts, so a one time use only bolt.
The downside to the ATI pulley, is you need to removed it, this means that the pulley bolts have to be removed to get it down to the inner hub, and the pulley bolts need to trashed and replaced before the unit is reinstalled. Hence it not only the initial torquing, but the 272 loctite that is used when they are installed, that ends up stretching the bolts as they are being removed, to cause them to snap after the fact, if you try to reuse them.
On the PB unit, since it has exposed threaded channel on the inner hub to pull it that way, it's easy to pull and reinstall it with just replacing the HB main bolt alone.
Note, tend to use the oem stretch to torque bolts, so a one time use only bolt.
Thread Starter
Burning Brakes
Joined: Jul 2002
Posts: 1,136
Likes: 100
From: Nova Scotia
That's good to know about the ATI, I never thought about that. Hopefully it'll be installed the once and forgotten about, but you never know what the future may bring. My biggest reason to go with the ATI over the PB is improved damping
Burning Brakes
Joined: Apr 2017
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Its not a harmonic balanced that is off center weighted to balance the motor out, but a harmonic dampening that is even weighted with dampening section/ring instead.
Hence LS motor is internally balanced, so the HD only dampens the off frequencies of the crank from the pulley instead.
So on that note, if you are looking to lighten a HD, then ATI would be the way to go, since before you assembly it, you can go through the parts to remove weight from each of them one at a time.
With something like the PB1117SS, you could still lighten it, but since it still has the Bonded OEM style rubber band between the inner hub and outer sections, you really don't want to remove the C ring pull it apart.
Short bus, since the flywheel has more weight that can be reduced, and will dictate more of how fast the motor will rev up, your just better off going with a lightened fly wheel on the other end of the motor if you want the motor to rev faster/pick up more power that way.
Hence LS motor is internally balanced, so the HD only dampens the off frequencies of the crank from the pulley instead.
So on that note, if you are looking to lighten a HD, then ATI would be the way to go, since before you assembly it, you can go through the parts to remove weight from each of them one at a time.
With something like the PB1117SS, you could still lighten it, but since it still has the Bonded OEM style rubber band between the inner hub and outer sections, you really don't want to remove the C ring pull it apart.
Short bus, since the flywheel has more weight that can be reduced, and will dictate more of how fast the motor will rev up, your just better off going with a lightened fly wheel on the other end of the motor if you want the motor to rev faster/pick up more power that way.
