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5.3 internal balance question

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Old Oct 11, 2018 | 09:47 PM
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Default 5.3 internal balance question

So I知 in the middle of my build, block is at the machine shop, all my parts have arrived except the supercharger. I知 have the machine shop balance the rotating assembly. They told me they will need the crank pulley and flywheel to do this. Since the LS is internally balanced, is this true? Since the supercharger pulley is different is that why they want it for balancing? I told them I知 just waiting on the supercharger to get here then I値l being all the components in, but if they don稚 need the crank pulley and flywheel to do the balancing then I値l just take the crank, pistons and rods up there and have them balance the **** now before the supe gets here. Thanks for any input.
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Old Oct 12, 2018 | 06:58 PM
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When I had my 302 ford balanced they wanted the crank pulley, balancer, flywheel, rods, pistons, and crank.
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Old Oct 12, 2018 | 10:27 PM
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Just don’t know why they want the crank pulley and flywheel since it’s an internally balanced engine and the pulley and flywheel have nothing to do with the balancing. I’m not against it, just don’t understand the theory behind it lol
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Old Oct 13, 2018 | 06:56 AM
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Most likely machine shop will spin the crankshaft and balance, then re-spin the crank with the balancer and flexplate (or flywheel & pressure plate) to ensure a zero balanced assembly. This eliminates the possibility of a bent flexplate, harmonic balancer wobble of the outer ring caused by rubber failure or someone getting happy with a sledge hammer or cheap aftermarket parts that aren't zero balanced etc. Once the engine (or parts) leave the machine shop they have no control of what may "unbalance" their work. If correct, this is good practice of dotting the i's and crossing the t's. I'm speaking in general not towards any parts you have or may not have. Why not ask the machinist himself to answer this question?



Originally Posted by Bgbldodge
When I had my 302 ford balanced they wanted the crank pulley, balancer, flywheel, rods, pistons, and crank.





It's my understanding fords are externally balanced with the balancer and flywheel assembly.

Last edited by RedXray; Oct 13, 2018 at 07:13 AM. Reason: edit to add
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Old Oct 13, 2018 | 11:38 AM
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They do not need the external parts if it's internally balanced. Think about that.

If they use the balanced and flexplate/flywheel in their balancing they are balancing the rotating assembly to potentially unbalanced components.

Does TSP, Or any of the other higher volume, high performance engine builders need those parts to balance an engine? Nope.

The crankshaft itself is spun and balanced, the rods are weighed and matched as are the pistons. When it's assembled it's balanced. It's a simple deal really.

Id question your builder and if he's offended or has any problem answering what you're asking (without feeding you bullshit) take your parts elsewhere.
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Old Oct 13, 2018 | 09:16 PM
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When you throw down big money, browsing through Texas Speed's online catalog... tell your machinist... "I don't believe you" It's says right here in Texas Speeds catalog" please listen! To reiterate again.. spinning of the balancer/flywheel after the crank balance is to foresee any issues beyond the crank balance itself. If you are not sure carry the Texas Speed catalog to your machinists and demand some answers.
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Old Oct 14, 2018 | 10:00 AM
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maybe he is old-school machinist used to small block chevy's and not LS based engines
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