i have two bigblocks and i have to say its twice as expensive and half as fun as an LSx engine.... the BBC looks and performs great,,, but you really have to shell out cash to get somthing good.. (and thats not a GM engine) my money would go towards a shafiroff untrastreet engine or a cammed LS3.. you can buy a 550 hp LS3 for about half the price of a 505 hp LS7.. and once you touch the ls7 the warranty is gone...
take a look at
www.mastmotorsports.com and simmilar enginebuilders... schwartz is also a good bet.. but im not sure what he chrages....