[TheRobb]

Most cast cranks from a name company are usually good to about 500 HP.
Above that, you want a forged crank.

As to the weight lightening, this is a very important thing to consider.

If your weight reduction is 17 pounds, then if you factor in the drivetrain gearing, and your total net reduction is 6 to 1 in first gear, then by lightening your reciprocating mass by 17 lbs, in first gear you get an overall effect or reducing the vehicle hole shot weight by 17x6. (circa 100lbs).
Isnt a 100 lbs worth a tenth of a second?

I think this is how it all works, not sure... either was told about this once or read about it somewhere, in regards to building race engines.

-Robb