Mitsubishi 6G72 crankshaft 1st gen cast iron. Balance factor (16). 

Checking the balance and measuring the balance factor as stock. The bobweights come in at about 840g.If I add or subtract any weight, the imbalance becomes worse. The speed is about 1200 rpm. So why bother? It weighs in at 15.30 ish Kg whilst the 2nd gen Steel crank weighs in at 16.80 kg. It's lighter, the counterweights are thinner so you could make the assumption that the bobweights would need to be lighter to balance it properly. I've already done the 2nd gen crank. The bobweights are somewhere between 830g and 850g These bobweights are 840g. Something's wrong? Using the weights of the factory parts, 840g bobweight comes out to close to 41% balance factor, working off 685g reciprocating and 556g rotating. The mathematics says that it should be close to 43.3% based on sine of 60 degrees is .8660