Grumpyvette: Do you have any articles on balancing V8 engines when all component weights are known and crank maximum bobweight is also known? Please advise. Thanks
will this help?
http://victorylibrary.com/mopar/crank-bal-c.htm
http://www.centuryperformance.com/engine-balancing-for-life-power-amp-efficiency-spg-145.html
http://www.torquecars.com/tuning/engine-balancing.php
http://www.eddiesvalvegrinding.com/balancing.htm
http://www.circletrack.com/tipstricks/4 ... index.html
http://www.circletrack.com/techarticles ... index.html
http://www.circletrack.com/techarticles ... index.html
http://www.completeautorepair.net/engine_balancing.htm
http://www.circletrack.com/enginetech/c ... index.html
http://www.babcox.com/editorial/ar/eb10330.htm
http://www.carcraft.com/howto/ccrp_0803_engine_balancing/index.html
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.
If your assembling a EXTERNALLY BALANCED 383 or 400 based engine,you'll need externally balanced flex-plate and damper components, obviously its best to have all components used balanced as a unit if possible
http://www.summitracing.com/parts/TFS-19001/
damper
http://static.summitracing.com/global/i ... ctions.pdf
damper install instructions
there are 153 and 168 tooth flex plates (12.8" and 14.1")and flywheels
youll need to get one that matches and is also externally balanced
if your using an INTERNALLY BALANCED crank and rotating assembly the damper and flywheel or flex-plate are at least in theory neutrally balanced and will have minimal effect on the total assembly, BUT if your crank and rods etc. are EXTERNALLY balanced I can,t see how the assembly CAN BE balanced without those components
related info
viewtopic.php?f=38&t=3900&p=13058&hilit=internally+externally#p13058
viewtopic.php?f=53&t=141&p=5391&hilit=internally+externally#p5391
viewtopic.php?f=53&t=259
viewtopic.php?f=53&t=89
viewtopic.php?f=53&t=204
viewtopic.php?f=53&t=6026
will this help?
http://victorylibrary.com/mopar/crank-bal-c.htm
http://www.centuryperformance.com/engine-balancing-for-life-power-amp-efficiency-spg-145.html
http://www.torquecars.com/tuning/engine-balancing.php
http://www.eddiesvalvegrinding.com/balancing.htm
http://www.circletrack.com/tipstricks/4 ... index.html
http://www.circletrack.com/techarticles ... index.html
http://www.circletrack.com/techarticles ... index.html
http://www.completeautorepair.net/engine_balancing.htm
http://www.circletrack.com/enginetech/c ... index.html
http://www.babcox.com/editorial/ar/eb10330.htm
http://www.carcraft.com/howto/ccrp_0803_engine_balancing/index.html
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.
If your assembling a EXTERNALLY BALANCED 383 or 400 based engine,you'll need externally balanced flex-plate and damper components, obviously its best to have all components used balanced as a unit if possible
http://www.summitracing.com/parts/TFS-19001/
damper
http://static.summitracing.com/global/i ... ctions.pdf
damper install instructions
there are 153 and 168 tooth flex plates (12.8" and 14.1")and flywheels
youll need to get one that matches and is also externally balanced
if your using an INTERNALLY BALANCED crank and rotating assembly the damper and flywheel or flex-plate are at least in theory neutrally balanced and will have minimal effect on the total assembly, BUT if your crank and rods etc. are EXTERNALLY balanced I can,t see how the assembly CAN BE balanced without those components
related info
viewtopic.php?f=38&t=3900&p=13058&hilit=internally+externally#p13058
viewtopic.php?f=53&t=141&p=5391&hilit=internally+externally#p5391
viewtopic.php?f=53&t=259
viewtopic.php?f=53&t=89
viewtopic.php?f=53&t=204
viewtopic.php?f=53&t=6026
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