My buddy just split his 347. It basically broke the hell out of everything. From the outside it just snapped the nose of the crank off. Once it all got taken apart, it was split down the lifter valley, a couple mains were broke off, two twisted rods and it was cracked all the way up the front of the block through the main bearing to the cam bearing and up to the lifter valley. It was literally almost tore in 2 halves.
BTW this was a 11.3:1 347, Victor heads, custom cam etc etc and it made 385/399 at the wheels, but then he got carried away and ran 6psi of Novi 2000 for about a week and his GTech said 499hp at the wheels and something like 450tq, and then it started running funny and smoking out the dipstick tube...he tore it down to find i think 2 blown pistons. He replaced those and left the blower off and a few months later the whole thing let loose. I think the blower cracked the block or something that he couldn't see when he replaced the pistons.
I split mine through all 3 webs from cam bore to main. The block didn't come apart, but the cam bearings were walking out which made the oil pressure plummet. No power adders, stock heads, about 250 RWHP. It's not the power, it's the rpm.