with trick flow a heads and approximately 850 horsepower. 14.5:1 compression and a cam of about 285 degrees of .050 so my peak power will be at around 6700-7000 rpm. i don't mind so much as to spend $1000 for the aluminum stuff because the motor will be all muscle, no joking gas or boost. of course strip only.
the eagle h beam rods are 810 grams for the 6.8 rod and there are some reports the the eagle rods can support up to 1000 horsepower. detonation and rpm is a factor though. in fact there's a local guy here by the name of brad tyson, and he use eagle h beam rods and eagle forged crank in 1200 rwhp 347 turbo (carb) motor. not to get off the subject but his car is badd and has ran a best of 7.8x on (stock suspension)!
Nearly any reasonable quality aftermarket rod will work fine at that power level and rpm in your 557. Scat, Eagle, Oliver I just don't think it matters all that much.
Aluminum rods have their advantages too in that they are lighter and that makes it easier to balance. Also at high horsepower levels they act like a shock absorber and are easier on the rest of the lower end, crank and bearings.
hmmm, a 605 c head motor; no cheap date for sure. i would definately love to have a c headed motor, or shucks just those heads for like a trophy or something. ha! ha! when fully worked over, how do the c heads match in terms with lets say the chevy big chief heads?