When the supercharged Ford 312's started kicking Chevy's butt in 1957, Chevy engineers came up with a 3-2BBL intake and a solid lifter cam and rushed the 348 medium duty truck engine into production in the 58 Impala to try to catch up. They had a nasty habit of swallowing valves above 5500 RPM. The 409 wasn't much better. The guys who were used to winding the 283's to 7000+ hated the 348!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!