I just got a 377 sbc motor from a neighbor. His brother built it, but is not to be found. The 400 block is cast #3951511, but it is a 2 bolt main. (replacement block?). This block has no steam vents between the "Siamese" cylinders. Since I have no heads, I thought I would use 350 heads as there are more of them around. The rub here is - does anyone know of 400 blocks that didn't have the steam vents. Also the block has the large oil passages on the left ban blocked. Anyone know what that is about. It's going into a 62 Vette, if I can figure all this stuff out.

tx