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Discussion Starter #1
What is the approx. cost to rebalance a BBC eagle forged crank with a bob weight of 2225 existing. The bob weight will be 2300 with the new rods and pistons.
 

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Can't get the rods and pistons lighter???????

If it has no holes in it.......... which it's an Eagle I am sure it does, but if not it will need heavy metal

If it has reasonable size hole, should be able to weld them shut............Hopefully

either way it won't be a $150.00 bill to do it........
 

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Discussion Starter #4
Its an internally balanced center counter weighted crank. Taking the bore from 4.320 to 4.5" to make a 540. Now by the time I get the valve clearance and dome shaped I may be able to cut the 75 gram difference in half.
 

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Discussion Starter #6
Can't answer that question right now. There are holes, the crank was one with a rough balance at a 2300 bob weight.
 

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You won't be able to cut that 75 gram difference in half just by grinding on the pistons. But honestly, you'll never notice that weight difference in the balance. Eagle guarantees that the crank is balanced to within 2% of the advertised bobweight. That's 46 grams with a 2300 bobweight, just to give you an idea of how far off it could be already. Some people use 2% overbalance, some 2% underbalance, and others use the exact bobweight. Balance is important, but I rank it down there with plug gaps or what brand valve cover gaskets to use.
 

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I would want it closer then 75 grams, I can tell you that.........

And heavy is not as good as lighter.................
 

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I must agree with RCM on this. 75 grams is about 2.6 ounces PER journal and in the wrong direction. :smt103
Do what is necessary to balance it where you want it % wise.

The words "Eagle guarantees...." just cracks me up.
 
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