Water passages on a 231 block

I've got a 231 I'm rebuilding and I'm wondering about what appears to be two water passages that have been plugged on the front of the block. They are long and thin, maybe two inches by 1/4 inch but completely plugged. Are these supposed to be opened? There was some passages that had some rust that I had to clear out but it all came out relatively easily.

I tried pressing on the plugged passage with a screw driver, it's quite solid. Should I open these? The heads are still out to have a head job so I can't compare to the heads.

 

Gotta pic? Worth a 1000 words......

 

Here's the pictures. One shows the open water passage and the other shows the one that looks like its plugged. There's an opening in the head gasket for it. Could this be the difference between a turbo and non-turbo block?

 

What's the head look like?

 

The head has openings on both sides, as does the head gasket.

 

I hope you're gonna have this block tanked. As far as the block have you run the serial number and casting numbers to see what year the block and heads are? May have heads off of a different year. Is this motor odd or even fire? Are the heads from a Dauntless or a 231?

 

Being totally clueless on the V6's I'll play the dummy and ask this question:
Will the heads from the Dauntless fit the 231?:?

 

Yes and no, the rockers oil thru a hole in the head on the 225 and the even fire 231 oils thru the push rods. The heads will physically bolt up but there are some years you can use others you can't do to water passages and such. I think in the tech section there is a list of differences that will allow you to tell which will and which won't.

 

The block has a casting number for an even fire 1979-1981 block, I don't know about the heads.

 

We did have the block tanked, the pictures are after it came back.

I don't know the head's casting number (the are at a friend's) but the block has 1261787 cast into it. From the list of casting numbers that's a 1979-1981 231 even fire.

 

from what i remember on my 225 and everything i have read on buick v6's,only the rear dogbone water passage is open. the heads and gaskets are open front and rear so they will fit either side of the engine block.

 

Ok, that's what I needed to know, thanks!