Thread: 377 Shortblock/400CI question

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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

Soooo, All 400SBC have water passages between the "siamese" cylinders and require steam holes to be drilled in 350 heads? Also I'm a bit lean on knowledge. What is "dizzy" boss on the block.---Facing the block on the drivers side at the very upper right of the block is the hole which is plugged, then on the bottom near the middle is another plugged hole. Why would that be done--to force more oil other places?

tx
bobvette62

In Streets Speak, Dizzy=Distributor

Pat

Thankyou, thankyou. I understand the "Dizzy" thing. I also understand that the steam vents exist between the siamese cylinders, but are separated. A steam vent exists on the intake side of joining of cylinders and on the exhaust side because water can not flow between them. BUT, did chevy make 400 blocks without the steam vents. I have a block without them, would you guys recommend drilling them in the block as well as the 350 heads which I will use, as marked by the 400 head gasket.

bobvette62