You would have to bore it .125 thousands to get it to a 4" bore. I highly doubt the 307 will take that much of an overbore and survive. Most blocks certainly can't be bored that much. 350 SBC are a dime a dozen. Better off just picking up one.
NO
Yes.
Pontiac didn't make a 307. If it's an Olds 307, you need an adapter or a BOP transmission.
Their the same
Well a 307 has a bore of 3.875 and a stroke of 3.25, so to build a 350 out of a 307 you would need to bore out the 307 .125 inch to a 4 inch bore, which in most cases can not be done, and you would have to put a 350 crank which has a stroke of 3.48 inches and use 350 pistons. But if you want more cubes and power out of your 307 you can bore it .03 over, have it decked .025 inches, and use a 350 crank with 400 rods and 307 pistons to make a ground pounding 333 stroker.
They are both internally balanced, so it should work.
chevy did not offer the ss package on 307 cid engine as far as I know they did offer it on the 350 cid how ever
It probably won't fit, so no. The 350 flexplate is far more common, so just get one of those.
Yes of course. All Chevy engines are interchangible with transmissions. For example, you can have a 305, 307, 327, 350, 400 with a turbo 350, turbo 400, or 700r4 big block are also the same
No. That would usually be a 283, 307, or 327.
As long as it is a B.O.P. transmission, yes. It will not bolt up to a Chevy engine without an adapter plate.
A small block Chevy has a 4inch bore. When you bore one 30 what you are doing is removing .30 thousandths from the cylinder. That would make the bore 4.030 or turn a 350cid into a 355cid.