Yes......

and Yes.....

 

yes almost everything on a sb chevy are interchangeable with each other

 

I'm also running a 305 and wondering if the blocks are the same, what is different? I know the heads are smaller, is the bore and stroke the same or is this where the differences are?

 

The bore is smaller on a 305. The stroke is the same as a 350.

The blocks are in the same family but are different because you CANNOT bore a 305 to the 350 bore size.

 

The only differences between a 305 and 350 is the size of the bore and the heads. While you cannot bore a 305 to a 350, everything else is interchangeable. I learned this in my quest for identifying the engine in my 81 GMC k1500, and found a really cool site for identifying parts on sbc. Check out nastyz28.com

 

i recently learned that the compression ratio on a stock 305 is 8.5 to 1. Is this also true of a 350 or not?

 

the compression ratio can vary from 8-1 to9-1 depending on the size of the chambers and the head gasket thickness.i run 58cc chambers and victor jr steel gaskets on my 305 my machine shop guy said it works out to around 9.5-1

 

One thing to look out for is the 87 up blocks.They use them funky lookin center bolt valve covers they have a differant intake pattern.The old intakes won't interchange with the newer ones.The newer ones have the center bolts angled differant.Atleast the ones I've seen have.
All the other old style intakes interchange 57-85.

 

You can slot the four center bolts to make the older intakes fit the newer heads and vice/versa.

 

So the old intakes will fit if you slot the four center bolts to make the older intakes fit the newer heads. could you please go into detail about that because i am new at this and would like to know thanks a bunch.

 

Be sure you don't try mixing vortec heads/manifolds with non-vortec heads/manifolds. They are different.