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Discussion Starter #1
On a 4.625 or 4.75 stroke Callies Magnum crank, will using aluminum rods still require heavy metal in the cranks counterweights?

If not it makes aluminum rods more economically attractive, as the balance job is cheaper.

Just wondering.
 

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Depends what the Bob weight of the crank is now. Who ever does your balancing can add up the rotating assembly now and tell you a target BW before spinning the crank. Your crank should be marked unless someone has fooled with it. If you had steel rods before and the crank was balanced aluminum will require less BW meaning the crank will need drilled or cut the counter weights.
 

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Discussion Starter #5
I appreciate the input guys.

The crank would come direct from Callies and thay can balance it if I give them a bobweight to balance to. Wasnt sure if it would be a $200 balance job or a $400 job with aluminum rods.

Im still on the budgetary fence of steel or aluminum rods and it crossed my mind.
 

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Better decide now if you want the expense of running aluminum rods before buying crank. If you choose to ever go steel one day you will need a whole lotta mallory and lots of money depending on rod. Sometimes there is not enough room left in the counterweights to put extra needed mallory in switching to steel rods for a crank built around less BW. You will save yourself alot of trouble knowing BW ahead of time letting Callie handle it.
 

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I have never had to run Mallory with these cranks or any other when balancing for aluminum rods outta the gate..switching to steel AFTER it was balancedfor aluminum is a whole different stopry and will need Mallory. Now if you are running a real heavy piston, that is a different story but it is not recommended with an alum rod to do so..Balancing won't be cheaper when compared to balancing with a steel rod the first time as no Mallory is really needed with most cranks and a light enough piston. And you don't have to replace them as often as you might think. With todays technology and material, they hold upo real well, but it is paplication specific that determines how long they will last..
 

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Discussion Starter #8
I have never had to run Mallory with these cranks or any other when balancing for aluminum rods outta the gate..switching to steel AFTER it was balancedfor aluminum is a whole different stopry and will need Mallory. Now if you are running a real heavy piston, that is a different story but it is not recommended with an alum rod to do so..Balancing won't be cheaper when compared to balancing with a steel rod the first time as no Mallory is really needed with most cranks and a light enough piston. And you don't have to replace them as often as you might think. With todays technology and material, they hold upo real well, but it is paplication specific that determines how long they will last..
What do you consider a heavy piston?
I will most likely use a Diamond 4.600" nitrous piston at around 690gr. plus pin and rings and locks.

....and do you know about what the ballpark bobweight is for a Magnum crank (4.625 or 4.750) that has had NO balancing done to it yet?
 
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