I agree with that also, most stuff on small block chevys will interchange. Most of the mercursers and Volvos are chevy type blocks as well. 265-400 sbc are interchangeable long as they are the older gen type. Some of the newer style block will work as well but not all of them. Most of the big blocks have the same bell housing as well but everything else is different. Your 305 has a 3.736 bore and a 3.480 stroke, where an 350 has a 4.000 bore and a 3.480 stroke (Bigger pistons). Also a 383 is just a 350 (3.480) with a 400 crank shaft (3.875) in it, same blocks. Everything else is basically the same. You are mainly limited by how much power you drive can handle. There are many crank rod piston rebuild kits out there available to stroke the 350s to get the extra inches. The 434 sbc I have is a aftermarket block that is a basicly a 350. It has 350 main bearings but it has thick piston sleeves that are boreable to 4.250 which with a 4.00 stroke crank will make a 454 small block! I had mine bored to 4.155 so I had more left if I ever needed to rebore it. The 4.00 stroke crank in a 400 block will give you 426 ci but it will need modifying to make it rotate. The rod bolts will hit the rails the oil pan bolts too. They make special pans to clear the rods but you would have to cut grooves in the block to clear the rotation of the rods. The 383 kits are a bolt in type, not much modifications needed and like said it dose not cause bad angles on the piston / rods. Most kits are sold with 6.0 rods which helps the angle instead of 5.7 in rods. You do have to have the right pistons to match for the longer rods. The pin in the piston is higher up to make it work out right. This helps get rid of bad geometry and binds the pistons less. Mercusier makes a nice stroker 383 motor that would be a good bolt in replacement. Islandtrader put one in his 21 moesly hull. Those are great for extra power and are still extremely reliable.
434 sbc I built:
