i ran into one of the retired ford engineers i used to work with. he just sold his original 427 Cobra and 351 pantera he bought with his employee discount. he said he gave the guy who bought the pantera some australian cylinder heads and webbers that he never installed. panteria's ran the truck 2 barrel 35l motor from the factory.which was of the same family as the 400. i have never seen anything in print abpout the austrailan 351=400 but the mexico 302's put out a lot more hp than good old smog approved usa stuff.