Engine Balance Factor

Wondering if it is common practice to overbalance your engines.
If anyone is doing it, how much overbalance are you using (52-54% ?), and have you noticed improvement on bearings or elsewhere ?

 

The whole purpose of overbalancing is to compensate for oil clinging to parts adding weight and ring friction that the crank FEELS as added weight.
The more ring tension the more overbalance needed.
More oil clearance the more overbalance needed to compensate for added oil weight on the reciprocating assembly.
Thats why lighter ring tension and oil control work togeather to make more power. (less rotating and reciprocatine friction)
Oil control prevents oil aeration and that makes bearings last longer.
Oil control allows less ring tension to keep the combustion chamber clean and detonation free. ( and that leads to a lot of questions on ring design )
It really is that simple.

 

ball park%

so do we assume that 52-54% would be in the ball park .just want to check this used crank that i have no history on......thanks

 

Here's the Yankee Stadium, % 52% When I raced I had my own engine balancer, and tryed all %'s , the oil is taken into consideration in the formala, over balancing is for reving over 8.500 rpm, after that rpm the engine goes into a differant harmonic balance, same as a tire that is out of bal. at 60 mph, smooth's out at 70 mph. P/S out of balance is what makes rods break because they shake/ vibrate, capish?

 

I would agree, we put alot of passes on our stuff and we "NEVER" over balance. Bottom line is one cylinder firing a little different"COULD" throw it out of balance but it wont. Remember if all the rings are sealed the drag would be the same, and besides they are all FASTENED to the same crankshaft. Balance it. be done. I would put the metal in the center if it were mine though... Just a thought.