I am considering an engine rebuild of a B20F engine. This is the 2.0 liter continuous fuel injection engine with over head valves. I have torn down the spare B21F engine I have and found the pistons are worn or were previously replaced with undersize pistons (perhaps from B19??). Replacement B20F pistons do not seem to be available. I have a couple of B21 engines which may or may not have useable pistons. I can buy B21 pistons and rings and could have the block bored to fit the larger (about .125 inch) pistons. My research shows that the stroke and connecting rods are the same for these engines. Deck height may be different - I have not found that level of detail.

Does anyone know if I can safely bore the B20F engine .125 inch over size? Can I use B21 piston in the bored B20F block without piston modification?

I am not looking for more power - just restore lost compression so my faithfull 1975 245 can go on like the energiser bunny............