Its an internally balanced center counter weighted crank. Taking the bore from 4.320 to 4.5" to make a 540. Now by the time I get the valve clearance and dome shaped I may be able to cut the 75 gram difference in half.
You won't be able to cut that 75 gram difference in half just by grinding on the pistons. But honestly, you'll never notice that weight difference in the balance. Eagle guarantees that the crank is balanced to within 2% of the advertised bobweight. That's 46 grams with a 2300 bobweight, just to give you an idea of how far off it could be already. Some people use 2% overbalance, some 2% underbalance, and others use the exact bobweight. Balance is important, but I rank it down there with plug gaps or what brand valve cover gaskets to use.