The 340 is the biggest POS V8 Chrysler ever made.

stock 340 A's had a window from about 30 to 85/90. When they hit 4th gear those 3.55s almost killed them.
I ALMOST got schooled by a 68-440 Chrysler New-something (Newport?). This high school friend of mine (brother to the girl I was going out with),his Dad had this great hulking beast of brown poo with a 440 auto, and he was going on and on and on and on about how fast it was. Wanted to race me for months. Finally I caved in; 30 to 85 I said; I knew my car's limits. You guessed it, I blew that barge for two gears. Then, on the way to 85, I watched that great whaling ship start catching up.I took him by a good bit, but I seen the handwriting on the wall. My Swinger went 98 in the qtr, and I'm 100% positive, had we raced to 98, that freighter woulda schooled me that day.
Not long afterwards,I put in some 4.10s .