Ford Repair: engine balance???, external balance, stroker kits

Question
Hi Steve
I been reading about the stroker kits that are avaible 331 or 347 for Ford... well theres something that Im not getting very well, and it is this with when they say that have to balance the parts.... what do they mean with balance, wich is the process to balance, wich parts of the car will need to balance..OOOO I also read about balance to 28 or 50 onze, I have a 1974 302ci wich is the proper onze to balance this early engine....well as you see this balance thing has me all mess up with my thoughts... I sure that you can clear them for me
Thanks very much
Rod.  

Answer
Rodrigo-

  Balancing is basically the process of evening out the weight of internal engine parts to reduce vibrations.  This is usually achieved by welding a metal (usually tungsten) onto the crank to balance it out with the weight of the rods and pistons.  It's not altogether too complicated, but it's an important step to making sure the engine is trouble free.  As for the external balance (the harmonic balancer), I believe your motor would use a 28oz. balance but I'm not positive about that.  Most of the time you'll just need to buy a balancer to match the balance of the rotating assembly.  Hope this helps.

Steve