Howdy Raymond:
Yes, a 250 cam will work in a 200. You must use 200 gears and chain as they are different.
You will note that the 250 cam has some clearance flat spots milled into the shaft in several locations for crankshaft clearance on the 250.
The early 250 grinds are very similiar to later 200 grinds at 256 degrees of duration. The later (80 & later) 200s are listed at .372" lift while the 250 show .368" lift.
FYI- these later 200 cams may be the best factory OEM cam, but be sure to use pre-'72 timing gear set for straight up cam timing. The later gears retard the cam timing for more low end and better emissions. Definately not better for performance.
Adios, David
