What was the ultimate "normal production" factory A Body?

I got my Swinger 340 new,, It was a great steet machine,, added all the speed goodies, running 2/10 ths off the NHRA record, and won lottsa hardware,,

At the strip, I can always remember pulling 2, 3, or 4 car lengths outta the hole, on BB Chevelles, BB Mopars and a nasty black GTO in particular,, only to watch them get closer and closer, and sometimes, pass me in the last 30 ft..

Won way more side $$ than I lost..

But you just can't beat cubic inch in the top end - - (naturally aspirated)