Question about engine balancing
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iTrader: (43)
Joined: Nov 2001
Posts: 2,669
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From: Pittsburgh, PA
Question about engine balancing I am rebuilding my engine. I had my rotating assembly balanced when I built my 408. Here is the question. I am reusing my crank and rods and bought new pistons for my 416. The new pistons are 7 grams lighter then my old ones. Is their a need to get it rebalanced and why??? I am looking at in in the respect that some carbon build up or oil on the piston would make more of a difference than 7 grams. Is it really necessary? I can see if the new pistons were 25 grams heavier or lighter but 7grams seemed pretty insignificant.
Staging Lane
Joined: Sep 2008
Posts: 66
Likes: 0
A properly balanced rotating assembly includes oil weight but not carbon build up. It should take a very long time to accumulate enough carbon build up to equal 1 gram in weight. 7 grams is a significant difference. You will never feel the vibrations but your rod and main bearings will.
see i am in the same boat as you. I took all my parts a machine shop to have checked/balanced with the new pistons. He said they were 8gr heavier then the old pistons and did not need to be rebalanced. I always thought it needed to be balanced every time, so i picked up my parts and now are with someone else getting finished.
