Been a while since my last post on here but Ive had a hella 2 months with engines breaking. Some of you guys may remember my 400 sm blk that I built up a while back. Anyways the air cleaner came loose and the 1/4-20 flat nut holding it on fell into the intake and landed on top of #5 piston between it and the deck. Say bye bye to the 400 Then a few weeks ago, my '97 chevy work truck broke a crank in the 350 vortec motor. I needed the truck badly so I ordered a new GM crate engine. It dawned on me that I could possibly build the vortec up for the replacement motor for the Jimmy. So I cracked open the oil pan this evening to have a look and the crank is cracked right through the 5-6 piston journal. (the piston rod was holding it together and why it would still run) But the engine is a 2-bolt main and I wanted to build up something with at least 400 HP. Asssuming that the vortec block is good which i have no reason to believe otherwise... My question is - should i look for a standard 350 4-bolt main block to build up or can I build this 2-bolt vortec up to 400 HP? What would you guys do?