I wonder how much the Eagle I-beams weigh? They're $250 @ mancini.
I spun some of those well past 8000 in a 302 ford (420 rwhp), but that was with sub 500 gram pistons, low tension rings, good bearings, blah blah. Shorter stroke so slower piston speed than a 340/360 also.
light stuff makes horsepower, but broken stuff makes for a really bad day.