Posted by: 286 Merc on the ford-trucks forum 11/19/02

The Packard was arguably the best engineered engine of its day. The head design was so good that GM bought the rights 10 years later. They were totally bummed and embarassed by the 409 at Daytona and needad an engine that would make power and stay together.
The result was the 65 Daytona 425 porcupine motor, in mid 65 it was the replacement for the 409 as the now famous 396 Rat Motor. I have a warmed over 396 in my 68 Impala SS-396 ragtop.