What happened, Corvette?

Actually, when looking the cars up, the Corvette seems to have not been offered with the 450 OR 460 HP engines. The highest HP rating I can find was the 425 HP LS6 454 in 1971.

Funny that in 1970, the 454 in the Corvette was rated at only 390 HP, but the Chevelle LS6 was rated at 450 HP. Now that I think about it, I know why. The Corvette's hood could not clear the Chevelle's high rise intake. I don't know what changes were made in 71, but obviously there were some.