Harmonic Balancer

[JLGO]

The harmonic balancer started to go bad in my cammed l99, is not making my car shake or anything like that but the a/c belt move a little to the middle of the balancer and it seems the balancer is wobbling. Any recommendations on which harmonic balancer to get? My idle rpm are between 850 to 900. Thanks

[zz430camaro]

For the price a Powerbond under drive is hard to beat. If price is no concern run a ATI Super Damper or Fluidampr.

[sixty9fordkiller]

an aftermarket damper of your choice is a must on these cars when you go with an aftermarket cam

the stock damper is not desinged to be spun beyond the factory rev limit on L99/LS3 cars

if you can already see that its wobbly, i wouldnt drive the car anymore until you have installed an after market one. Your hood and a bunch of other parts will thank you


this rubber that their speaking about here, is what has llikely started failing on yours. get it done before it flies of

[Chris49066SS]

I run the Powerbond damper with the SS4 cam, no problems here

[1JEWLDSSRS]

I run the Powerbond with TSP stage 3 cam..

[christianchevell]

I run the Fluidampr and do not underdrive the A/C also it makes sure to dampen vibrations harmful to the engine, the instruction include the right length for the belt but not the right gates number as some other good $$$ like ATI may be wrong number also etc. Don't go cheap you might as well use the paper weight stock POS. Seen them fall apart on here over the years not pretty, along with the cheap rubber isolation ringed crappy under drives also fall apart. BTW underdrives usually make no real power gain, you can with a gain in idle go under on the alternator. I recommend the nice starter I use now also. https://www.summitracing.com/parts/p...t/model/camaro the power master xs 9509 kicks the stock starters ARSE royally dealing with heat soak......

[sixty9fordkiller]

i run an ATI

its 10% underdrive and works with the stock belt.

[Nb1081]

Ive had machine shops refuse to balance a rotating assembly with a fluidampr because they can gel up and throw the balance way off

[christianchevell]

The rotating assembly is pre balanced internally on a ls engine just not perfectly BTW... and no one balances aftermarket internals either with a balancer unless your externally balanced; its just for removing vibrations. Now if you a old crappy balanced SBC or something you have the stock chunk out front which smart people even then internally balance the engine and use better aftermarket balancers...built enough of them, I'm old. But for cheap most just do stock internals and the stock two piece balancer which it needs, and it be depending on what its made as.....old chevy GUY here...… two piece or one piece main etc, what size bbc or sbc…..etc etc we are internally balanced in a ls read this and understand the balancer should make no difference in it balancing at all, its for stopping vibrations. now weighted a balancer and or flexplate/fly wheel can make a difference to externally etc... balanced engines big time.

What’s the difference between internal and external engine balance?

Engine Balance: Internal vs. External
An engine must be balanced to ensure smooth operation. It minimizes vibration and maximizes engine life. Balancing can be internal, external, or a combination of both.
Balancing an engine means offsetting the weight of the pistons and rods. This involves adding or removing weight from the crankshaft. The Harmonic Balancer and/or the flexplate or flywheel can also be weighted.
Internal Balance
An internally balanced engine has all the counterweight on the crank. External parts like the balancer and flexplate/flywheel have a neutral balance. They will not affect the other rotating parts.
External Balance
If the crank's counterweights are too light, the engine must be externally balanced. This involves adding weight to the harmonic balancer and/or the flexplate or flywheel.
How does it affect performance?
Generally speaking, internal balance is the better option. External counterweights can cause the crankshaft to flex at high rpm. This can cause engine damage. However, either type of balance is fine for most engines.
Converting from external to internal balance can be expensive. It requires a new crankshaft, harmonic balancer, and/or flywheel or flexplate. You may also need to clearance the block for the larger counterweights. Unless you're racing, it's easiest to balance the engine the same way the factory did.
Engine Type
Factory Balance Method
Chevy 305/350 (2-piece rear main seal)
Internal
Chevy 396-427 Big Blocks
Chevy LS Engines
Ford Modular Engines
Chevy 400/454
External
Ford 302/351W
Chevy 350 (1-piece rear main seal, including LT1)
Combination of Internal & External

Notes
Balanced Rotating Assemblies come pre-balanced from the manufacturer. These can be installed without taking the parts to the machine shop.
If you buy an Unbalanced Rotating Kit, you will need to have it balanced before it's installed. The same is true if you buy a crankshaft, connecting rods, and pistons separately.
Crankshafts are listed as internal or external balance. This doesn't mean it's already balanced. It just tells you how it's intended to be balanced. It must be checked with the specific piston and rod combination you use.
https://help.summitracing.com/app/an...ine-balance%3F

https://fluidampr.com/types-of-harmonic-balancers/

A nice wide range balancer can make a big difference in the longevity of a engine, and that matters so much more when they cost $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

[Chris49066SS]

There he is, I haven't seen one of those long write ups from ol christianchevelle in a hot second but figured he would chime in on the damper

[JLGO]

Lol, good write up. I was going to replace the harmonic balancer before I even had thE TSP VVT3 cam installed. I had the same woble issue with my L98 back in the day. My L99 is wobbling just a little more than before that is why the ac belt shifted a little from the crank pulley.

I only drove my car about 6k miles since the cammed install and has been about 14 months since. I am undecided about the HB. Please help

[suprchrgd]

Originally Posted by christianchevell

The rotating assembly is pre balanced internally on a ls engine just not perfectly BTW... and no one balances aftermarket internals either with a balancer unless your externally balanced; its just for removing vibrations. Now if you a old crappy balanced SBC or something you have the stock chunk out front which smart people even then internally balance the engine and use better aftermarket balancers...built enough of them, I'm old. But for cheap most just do stock internals and the stock two piece balancer which it needs, and it be depending on what its made as.....old chevy GUY here...… two piece or one piece main etc, what size bbc or sbc…..etc etc we are internally balanced in a ls read this and understand the balancer should make no difference in it balancing at all, its for stopping vibrations. now weighted a balancer and or flexplate/fly wheel can make a difference to externally etc... balanced engines big time.

What’s the difference between internal and external engine balance?

Engine Balance: Internal vs. External
An engine must be balanced to ensure smooth operation. It minimizes vibration and maximizes engine life. Balancing can be internal, external, or a combination of both.
Balancing an engine means offsetting the weight of the pistons and rods. This involves adding or removing weight from the crankshaft. The Harmonic Balancer and/or the flexplate or flywheel can also be weighted.
Internal Balance
An internally balanced engine has all the counterweight on the crank. External parts like the balancer and flexplate/flywheel have a neutral balance. They will not affect the other rotating parts.
External Balance
If the crank's counterweights are too light, the engine must be externally balanced. This involves adding weight to the harmonic balancer and/or the flexplate or flywheel.
How does it affect performance?
Generally speaking, internal balance is the better option. External counterweights can cause the crankshaft to flex at high rpm. This can cause engine damage. However, either type of balance is fine for most engines.
Converting from external to internal balance can be expensive. It requires a new crankshaft, harmonic balancer, and/or flywheel or flexplate. You may also need to clearance the block for the larger counterweights. Unless you're racing, it's easiest to balance the engine the same way the factory did.
Engine Type
Factory Balance Method
Chevy 305/350 (2-piece rear main seal)
Internal
Chevy 396-427 Big Blocks
Chevy LS Engines
Ford Modular Engines
Chevy 400/454
External
Ford 302/351W
Chevy 350 (1-piece rear main seal, including LT1)
Combination of Internal & External

Notes
Balanced Rotating Assemblies come pre-balanced from the manufacturer. These can be installed without taking the parts to the machine shop.
If you buy an Unbalanced Rotating Kit, you will need to have it balanced before it's installed. The same is true if you buy a crankshaft, connecting rods, and pistons separately.
Crankshafts are listed as internal or external balance. This doesn't mean it's already balanced. It just tells you how it's intended to be balanced. It must be checked with the specific piston and rod combination you use.
https://help.summitracing.com/app/an...ine-balance%3F

https://fluidampr.com/types-of-harmonic-balancers/

A nice wide range balancer can make a big difference in the longevity of a engine, and that matters so much more when they cost $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

Any chance you would have a phone conversation with me?

[zz430camaro]

Its not that big of a deal, just pick one and buy it.

[suprchrgd]

Originally Posted by zz430camaro

Its not that big of a deal, just pick one and buy it.

i know,lol. i want to talk about his 427 stoker setup. he doesn't accept pm's, so I was hoping this would get me in touch with him