If you do decide to go with a SC'd 347 be careful with the RPM's and the amount of boost. I know a few of you said that you have never seen an engine split, but I have. I have a real good friend that had a SC'd 331 that he split. It can and will happen if you abuse the engine to much. His was in a drag car that got beat on pretty regular. If you keep the boost and RPM's at a decent level and don't try to squeeze every little bit out of your combination, it could last you for a good long time.