I tried a search but wasn't able to find any awnser in the 600+ responses! A friend of mine has a C3 Corvette with a powerless reman engine. He just got a 350 from a mid 90's truck. He said it's a Vortec 5.7L and asked what the difference was between a normal SBC and a Vortec. I told him I believe the block is no different than what he's got and I thought the difference was in the heads but I couldn't say what's different about them. It's has centerbolt calve covers, and it was free, that's all I know! Sorry for the newb question, I'm not familar with much of anything but LT/LS engines! ops:
If you look in the intake port of the Vortec head VS a STd head the vortec had a point in the runner to swirl the air before entering the chamber, other then that just the valve cover bolts.