I remember watching the 1971 NHRA Winternationals stock qualifying in the classes the 340 ran in, the 1971 where quiet a bit faster than the 1970 cars in the same classes I didn't know at that time that the 1971 340 had different carbs than the 1970s did NHRA put the 1971 cars in the higher classes, weight per HP rules, later that year I beleive