no not at all, i was just curious, someone recommended 23 degree pontiac heads, i was told that a certain set flowed 340 out of the box, i didn't really want to fool with any degree heads (18,15,12) right now but i might have to go that way. I was also told to check out the sb2.2, i wanted to put the heads on a jay dickens chevy 434 that i drag race.