Except for the additional 50 cubes and the ability to use V8 transmissions, the 250 has very little advantage over the 200.
Pretty much anything that fits a 250 can fit a 200: heads, intakes, exhausts, pistons (except 255), and cams.
Parts that you can get for the 200 that you can't get for the 250 is a double roller timing chain and deep sump oil pan.
Of course, I'm talking about the US engines.
jb1rd
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