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It has been a while but I do know for a fact that the inline 5cyl is externally balanced. Now what this means is there was not enough material on the crank to successfully balance and addition weight had to be added out side of the crankcase. (flywheel and balancer)
I don't remember exactly how much but it is between 20 and 35 grams.

Also when balancing the inline 5cyl the formula for finding the correct bobweight and that is using 50 percent of the reciprocating weight.

Which means taking 100 percent of the rotating weight (big end of con rod and bearing) and 50 percent of the reciprocating weight (small end of con rod, piston, pin, rings, and locks) and placing this calculated weight on the each rod journal of the crank and spinning the assembly.

This is necessary as the pistons are at different positions as the engine is running. This is why it is ideal to have the rotating assembly balanced when changing rods or pistons on a 5cyl.

On inline 4 cyl there is no need for a bob weight because as one piston and rod assembly is coming down the other is going up which in theory cancels the out the weight. Not so on the 5cyl.

Most american v8 are usually lucky to be within 25 grams of imbalance. So you probably could just slap on a zero balance flywheel and balancer and may not feel the difference. But your rod and main bearings will thank you in the long run.

As far as balancing the clutch assembly I prefer to balance as complete assembly, balancer, flywheel, and pressure plate. I just think the balance comes out better. I will always zero the rotating assembly then bolt on and balance the pressure plate. That way if it needs to be swapped out at a later time it won't affect the overall balance as much. I have once found a brand new Centerforce pressure plate to be out of balance by 50 grams and this was for a late model corvette. After coming across this I will not balance a rotating assembly with out the pressure plate.
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