[bmalone]

Clois, the 406 had a short life; from '61 - '63. In terms of development, it was the predecessor that lead directly to the 427 CO. It was run in NASCAR. It was a race-oriented motor from the outset. Consider that it made peak HP at 5800; kind of tells you its orientation. 11.7:1 CR and 405 HP w/ 6v or 385 w/ 1v. Opening the bore was the next logical step--hence the 427.