440 vs 383

The parts that are interchangeable are the heads, rocker arms and shafts, camshaft, waterpump and oil pump. Like the guys say, there are a lot of questions that need answers before recommendations and a few more are what are the casting numbers on the 383 and 440 heads and especially the year of 440. If it's a low compression engine pistons and maybe block decking may be in order.

Terry